Auger electron yields of metastable Li-like projectile states repopulated by radiative cascades and Auger depletion Manolis Benis Department of Physics, University of Ioannina SPARC.
Download ReportTranscript Auger electron yields of metastable Li-like projectile states repopulated by radiative cascades and Auger depletion Manolis Benis Department of Physics, University of Ioannina SPARC.
Slide 1
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 2
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 3
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 4
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 5
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 6
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 7
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 8
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 9
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 10
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 11
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 12
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 13
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 14
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 15
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 16
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 17
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 18
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 19
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 20
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 21
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 22
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 23
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 24
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 25
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 26
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 2
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 3
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 4
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 5
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 6
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 7
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 8
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 9
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 10
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 11
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 12
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 13
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 14
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 15
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 16
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 17
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 18
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 19
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 20
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 21
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 22
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 23
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 24
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 25
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015
Slide 26
Auger electron yields of metastable Li-like projectile states
repopulated by radiative cascades and Auger depletion
Manolis Benis
Department of Physics, University of Ioannina
SPARC workshop, Fodele, September 22-27, 2015
Ion-atom Collisions
Atomic
Energy
levels
continuum
Ea - Auger energy
e-e interaction M
L
Ex
K
capture
K
ionization
K-M
excitation
M-K
radiative
transition
K
KLM
Auger
transition
Ion-atom collision
e-
e-
vt
Zp
Vp
b
Projectile
Ion
Charge q+
Zt
Target
Atom
SPARC workshop, Fodele, September 22-27, 2015
Atomic Structure: q, Zp, Zt , Ex, Ea…
Collision Dynamics: b, Vp , vt …
Cross section: (Vp , q, Z p , b, vt , Zt , Ea , Ex ,...)
Highly Charged Ions: Few-electrons - simpler
environment for testing theories
Highly Charged Ions
Basic understanding of atomic collision processes
QED corrections
Astrophysical plasmas
Cometary X-ray emission
Fusion research
Radiation damage
HCI nano-structuring of surfaces
Guiding of HCI in insulator nano-capillaries
Accelerator physics
Instrumentation R & D
SPARC workshop, Fodele, September 22-27, 2015
Projectile Spectroscopy
Control of the number of electrons on the projectile
Fewer electrons Less complicated system
Metastable ionic beams
Easy to study iso-electronic sequences
C3+(1s22s), B2+(1s22s), Be+(1s22s) , …
Low-Z projectiles High Auger electron yields
Kinematic advantages
Zero-degree Auger Projectile Spectroscopy (ZAPS)
SPARC workshop, Fodele, September 22-27, 2015
Populating the 1s2l2l' states
T (or C)
V
RTE
V
NTE
V
Target
Projectile
SPARC workshop, Fodele, September 22-27, 2015
Spin statistics for 2p capture to 1s2s 3S
Spin recoupling
Probability
4
(1s(2s 2 p)3 P) P
6
4
(1s 2s S )2 p P
6
3
4
4
3
1s 2s S + 2p
1
(1s(2s 2 p) P) P
4
3
2
(1s 2s S )2 p P
6
3
Final
breakdown
4P
2
: 2P- : 2P+
8
1
3
12 12 12
SPARC workshop, Fodele, September 22-27, 2015
2
4
3
(1s(2s 2 p) P) P
4
P
R 2
2
2
P P
1
2
P
R 2 3
P
2
Literature Overview
7
Lee (1991)
Tanis (2004)
6
4
2
2
Ratio - R = e( P)/[e( P+) + e( P--)]
Data:
5
4
3
2
1
7+
2
3
F (1s /1s2s S) + He
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
2
Ratio - R = e( P)/[e( P+) + e( P--)]
7
5
4
2
Spin statistics
6
4
3
2
1.875
1
7+
2
3
F (1s /1s2s S) + H2
0
Strohschein et al, PRA 77 022706 (2008)
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
Projectile Energy (MeV/u)
Zouros et al, PRA 77 050701 (2008)
SPARC workshop, Fodele, September 22-27, 2015
Pauli exchange interaction (?)
A target electron with spin aligned to the spin
of the 1s projectile:
a) can be captured into the 2p directly to form
the 1s2s2p 4P
b) cannot be captured into the 1s (or 2s) due to
Pauli exclusion.
Tanis et al, PRL 92 133201 (2004)
New idea: So instead it interacts with the 1s (or
2s) via a Pauli Exchange Interaction with one etransferred to the 2p forming additional 4P
states
The Pauli Exchange Interaction is reminiscent of the Transfer-Excitation mechanism,
but with two identical electrons doing the Transfer and the Excitation!
- Rather puzzling and difficult to calculate (not possible to date!)
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
nl
Zouros et al , PRA 77 050701 (2008)
Significant capture to higher n=3-7
indicated by CDW calculations
SPARC workshop, Fodele, September 22-27, 2015
Radiative Cascade feeding (?)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Ne
d
ddE N I n l 0 E T
2
4MeV B 3+ [1s2 1S, 1s2s 3S] + H2
Capture
RTE
No lifetime/solid angle corrections
Benis et al, PRA 65 064701 (2002)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
22
1s2s S
8
6
22
2
1
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
“Subtract” spectra to obtain pure metastable
beam 1s2s 3S spectrum!
-20
2
4
2
10
3
3
1s(2s2p P) P
f S = 25%
4
12
cm / eV sr)
Mixed state (1s2, 1s2s 3S) spectrum
25% metastable
Ion Beam obtained by foil stripping
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
Practically ground state (1s2)
spectrum. < 3% metastable
Ion Beam obtained by gas stripping
at lower energies
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
Mixed state (1s2 1S, 1s2s 3S ) beams
Strohschein et al, PRA 77 022706 (2008)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid correction factor
Ne
d 2
ddE N I n l 0 E T
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Hemispherical Deflector Analyser
12MeV C3+(1s2s2p 4PJ )
The effective solid angle correction factor
Hemispherical Deflector Analyser
SIMION Monte Carlo type Calculations
2.0
SIMION
Analytical
o
(max= 2.2 )
F=4
s0= 289 mm
4
Electron Signal (Arb. Units)
5
G
3
2
1
0
1
10
2
10
3
10
VP (mm)
4
10
max = kinem= 40.3
1.5
1.0
max = 2.0
o
max = 1.8
o
max = 1.5
o
max = 1.0
o
o
SIMION
F=4
4
P
0.5
0.0
225
226
227
228
229
230
231
232
Auger Electron Energy (eV)
Benis et al, NIMB (2015) In press
The lens filters out emitting angles higher than 2o
The lens also filters out electrons generated within it …
SPARC workshop, Fodele, September 22-27, 2015
233
SIMION simulations
Doukas et al, Rev. Sci. Instr. 86 043111 (2015)
SPARC workshop, Fodele, September 22-27, 2015
Revisit of older data
22
1s2s S
8
6
4
1
22
2
2
1s2p D
+ H2
2
0
14
12
f S < 3%
3
10
2
d /dd (10
-20
2
cm / eV sr)
10
3
3
1s(2s2p P) P
f S = 25%
4
12
1s2s2p P
14
1s(2s2p P) P
3+
4 MeV B
8
6
4
2
0
150 152 154 156 158 160 162 164 166 168 170
Electron Energy (eV)
Benis et al, PRA 69 052718 (2004)
SPARC workshop, Fodele, September 22-27, 2015
The effective solid angle correction factor
Ne
d
ddE N I n l 0 E T
2
Tandem Parallel Plate Analyser
A spectrometer with well defined solid angle
L2
?
w
l
S
-4
5.0x10
Geometrical
SIMION
-4
4.0x10
(sr)
-4
3.0x10
d
-4
2.0x10
-4
1.0x10
x
0.0
100
80
60
40
x (mm)
SPARC workshop, Fodele, September 22-27, 2015
20
0
L1
Cascade Feeding and depletion of a state
Order
depopulation
population
Curtis, Am. J. Phys 36 1123 (1968)
SPARC workshop, Fodele, September 22-27, 2015
More SIMION simulations …
Include cascade feeding theoretical calculations in the Monte Carlo SIMION simulations
4+
21
Direct comparison to
the experiment!
(No correction factors …)
3
12 MeV C [1s S, 1s2s S] + He
4000
4
3500
SIMION
Second order cascades
First order cascades
No cascades
P
Electron Counts
3000
2500
2000
2
1500
S
2
2
1000
P+
P_
Testing ground
2
Y ( 4P) / G
2
2
2
Y ( P ) Y ( P )
D
500
0
222
224
226
228
230
232
234
236
238
Auger Electron energy (eV)
Calculations by T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
240
242
244
Spin statistics for 2p capture to 1s2s 3S
SPARC workshop, Fodele, September 22-27, 2015
Mid-Future Prospects
SPARC collaboration:
Extend our studies to high(er) Z elements
Locate candidate metastable electronic configurations
LS jj coupling nomenclature, theorists help
Develop a TDR
Current electron spectrometer in a new setup (UHV chamber, gas jet, etc.)
Get approved and … Ask for funding …
SPARC workshop, Fodele, September 22-27, 2015
Current and near-future prospects
Investigation of the systematics of the 4P/2P ratio in an
isoelectronic sequence study using He-like ions from Li+ , B3+ ,
C4+ , N5+ , O6+ , F7+ in the 0.1-2 MeV/u
Use different targets such as H2, He, Ne, Ar
In progress:
•
Installation of terminal gas stripper to
produce ground state beams
•
Installation of post strippers (foil and gas)
to produce He-like ions at lower energies
SPARC workshop, Fodele, September 22-27, 2015
Ongoing Research
New targets
Higher Energy – 18 MeV
6
6
4
5
W=1521eV,F=4,
VL4 =-684.45V,
VL5=1399.32V
Ne
2
0
-11
4
2
4
P
2
S
He
2
P-
2
P+
P
4+
18 MeV C
W=1521eV, F=4
Ne (20 mTorr)
Fit
4
2
2
D
3
4
2
2
2
2
P
2
D
2
2
S
0
6
P-
5
Ar (5 mTorr)
Fit
4
P
4
P
3
2
P+
2
S
1
P-
2
D
0
2
D
2
1
220
H2
2
Ar (5 mTorr)
Fit
4
4
2
Norm.yields
Norm.fit
P+
0
3
2
0
W=1966eV, F=4
1
2
P-
S
1
P+
4+
Ne (20 mTorr)
Fit
-11
Normalized electron Yields ( 10 )
12 MeV C
4+
4
Normalized electron Yields (x10 ) (arb.units)
3
12 MeV C
2
2
S
2
P-
P+
2
D
0
225
230
235
240
245
250
220
225
230
235
240
245
250
Auger Electron Energy (eV)
0
4
Ar
2
0
220
225
230
235
240
245
Auger electron Energy (eV)
SPARC workshop, Fodele, September 22-27, 2015
250
New calculations are needed
to evaluate capture and cascade
contributions for all measured
collision systems
The People
5MV Tandem NCSRT Demokritos, Greece
Dr. S. Harissopulos (Director),
A. Lagogiannis, M. Axiotis, M. Andrianis
University of Crete, Greece
Prof. T.J.M. Zouros
A. Dimitriou (Post doc), I. Madesis (PhD),
A. Laoutaris (MSc), Ch. Nounis (MSc)
University of Ioannina, Greece
Prof. M. Benis
S. Doukas (MSc)
Universidade Nova de Lisboa, Portugal
Prof. J.P. Santos,
Prof. F. Parente,
Prof. M.C. Martins
Sorbonne Universités, Paris, France
Prof. P. Indelicato
Funded by the APAPES Project:
http://apapes.physics.uoc.gr/
ATOMKI, Debrecen, Hungary
Prof. B. Sulik
University of Isparta, Turkey
Prof. O. Sise
York University, Toronto, Canada
Prof. T. Kirchner
SPARC workshop, Fodele, September 22-27, 2015
Co-financed by the European Union and Greek national
funds through OP: Education and Lifelong Learning,
Research Program: THALES Grant # MIS 377289
Thank you for your attendance
Acknowledgement: This research has been co-financed by the European Union (European Social Fund ESF) and Greek national funds through the
Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) Research Funding Program:
THALES. Investing in knowledge society through the European Social Fund, grant number MIS 377289.
SPARC workshop, Fodele, September 22-27, 2015