Transcript Coulomb Excitation of Neutron Rich Zn Isotopes with the

Title page
Coulomb Excitation of Neutron Rich Zn Isotopes
J Van de Walle1, I. Stefanescu1, P Mayet1, O Ivanov1, F Aksouh1, D Smirnov1, JC Thomas1, R Raabe1,
M Huyse1, P Van Duppen1
1
IKS KULeuven Belgium
O Niedermaier2, M Lauer2, V Bildstein2, H Scheit2, D Schwalm2, N Warr3, D Weisshaar3, J Eberth3, M Pantea4, G Schrieder4, O
Kester5, F Ames5, T Sieber5, S Emhofer5, B Wolf5, R Lutter5, D Habs5, P Butler6, J Cederkall6, P Delahaye6, S Franchoo6, Y
Kojima6, U Koster6, T Nilsson6, F Wenander6, J Iwanicki7, A Hurst7, F Azaiez8, F Ibrahim8, O Perru8, M Stanoiu8, O Sorlin8, D
Verney9, Th Behrens10, Th Kroll10, R Krucken10, G Sletten11, the MINIBALL collaboration and the REX-ISOLDE collaboration
2
Max Planck Institut fur Kernphysik Heidelberg Germany
3 Institut fur Kernphysik Universitat Koln Germany
4 TU Darmstadt Germany
5 LMU Munchen Germany
6 CERN Switserland
7 University of Liverpool Great Britain
8 IPN Orsay France
9 GANIL Caen France
10 TU Munchen Germany
11 Neils Bohr Institute Roskilde Denmark
Physics Motivation
Experimental Setup
Experimental Results
Physics
Motivation
Phys Mot
(Chart)
N=40, 50
74,76,78Zn
(Z=30)
Z=28
78Ni
Coulomb Excitation of Neutron Rich Zn Isotopes
Jarno Van de Walle
Physics Motivation
Experimental Setup
Experimental Results
Physics Motivation : Ni
Ni isotopes
Phys Mot (Ni)
50
50
g9/2
g9/2
40
28
40
p1/2
p1/2
f5/2
f5/2
p3/2
p3/2
28
40
28
f7/2
f7/2
20
20
protons
neutrons
Z=28
N=28...40
Langanke et al, PRC 67, 2003
Sorlin et al, PRL 88, 2002
Broda et al, PRL 74, 1995
68Ni
Coulomb Excitation of Neutron Rich Zn Isotopes
Jarno Van de Walle
Physics Motivation
Experimental Setup
Experimental Results
Physics Motivation : Zn
Ni isotopes
Zn isotopes
Phys Mot (Zn)
50
50
g9/2
g9/2
40
28
40
p1/2
p1/2
f5/2
f5/2
p3/2
p3/2
28
40
Ganil,
intermediate energy coulex
28
f7/2
f7/2
20
20
protons
neutrons
Z=28
N=28...40
72Zn
Coulomb Excitation of Neutron Rich Zn Isotopes
Leenhardt et al, EPJA 14, 2002
“Onset of Deformation”
1-Additional protons outside N=28
2-Neutron pairing interactions maximal at N=40
Jarno Van de Walle
Physics Motivation
Experimental Setup
Experimental Results
Physics Motivation : Ge
Ni isotopes
Zn isotopes
Ge isotopes
Phys Mot (Ge)
50
50
g9/2
g9/2
40
28
40
p1/2
p1/2
f5/2
f5/2
p3/2
p3/2
28
40
?
28
f7/2
f7/2
20
20
protons
neutrons
RIKEN
Intermediate energy coulex
Iwasaki et al, private communication
Z=28
50
N=28...40
82Ge
Coulomb Excitation of Neutron Rich Zn Isotopes
Oak Ridge
Low energy coulex
Padilla-Rodal et al, PRL 94 122501 (2005)
Jarno Van de Walle
Physics Motivation
Experimental Setup
Experimental Results
Experimental Setup : REX-Isolde
REX-Isolde + "Miniball"
Exp Setup 1
since 2001 :
30Mg ( PRL 94, 172501 (2005) ) 32Mg
74,76,78Zn
110Sn (poster A. Ekström)
122,124Cd
70Se
84,86,88Kr
* selective : laser
* efficient
* fast
Coulomb Excitation of Neutron Rich Zn Isotopes
Jarno Van de Walle
Physics Motivation
Experimental Setup
Experimental Results
Experimental Setup : REX-Isolde 1/5
1. Target : UCx (74Zn,76Zn) + neutron converter (78Zn)
Exp Setup 1bis
Coulomb Excitation of Neutron Rich Zn Isotopes
Jarno Van de Walle
Physics Motivation
Experimental Setup
Experimental Results
Experimental Setup : REX-Isolde 2/5
Exp Setup 2
1. Target : UCx (74Zn,76Zn) + neutron converter (78Zn)
2. Laser Ionization of Zn (RILIS) + Mass separation (GPS)
Coulomb Excitation of Neutron Rich Zn Isotopes
Jarno Van de Walle
Physics Motivation
Experimental Setup
Experimental Results
p
S
et
u
p
3
Experimental Setup : REX-Isolde 3/5
1. Target : UCx (74Zn,76Zn) + neutron converter (78Zn)
2. Laser Ionization of Zn (RILIS) + Mass separation (GPS)
3. Bunching (REXTrap) + Charge Breeding (EBIS)
Coulomb Excitation of Neutron Rich Zn Isotopes
Jarno Van de Walle
Physics Motivation
Experimental Setup
Experimental Results
Experimental Setup : REX-Isolde 4/5
Exp
Setup
4
2. Laser Ionization of Zn (RILIS) + Mass separation (GPS)
1. Target : UCx (74Zn,76Zn) + neutron converter (78Zn)
3. Bunching (REXTrap) + Charge Breeding (EBIS)
4. Post Acceleration :
Coulomb Excitation of Neutron Rich Zn Isotopes
~2.87 MeV/u
Jarno Van de Walle
p
S
e
t
u
p
5
Physics Motivation
Experimental Setup
Experimental Results
Experimental Setup : REX-Isolde 5/5
1. Target : UCx (74Zn,76Zn) + neutron converter (78Zn)
2. Laser Ionization of Zn (RILIS) + Mass separation (GPS)
3. Bunching (REXTrap) + Charge Breeding (EBIS)
4. Post Acceleration :
~2.87 MeV/u
5. Coulomb Excitation : Miniball + DSSD

j
q
Coulomb Excitation of Neutron Rich Zn Isotopes
Jarno Van de Walle
e
t
u
p
5
b
i
s
Physics Motivation
Experimental Setup
Experimental Results
Experimental Setup : REX-Isolde 5/5
1. Target : UCx (74Zn,76Zn) + neutron converter (78Zn)
2. Laser Ionization of Zn (RILIS) + Mass separation (GPS)
3. Bunching (REXTrap) + Charge Breeding (EBIS)
4. Post Acceleration :
~2.87 MeV/u
5. Coulomb Excitation : Miniball + DSSD
Coulomb Excitation of Neutron Rich Zn Isotopes

j
q
Jarno Van de Walle
Physics Motivation
Experimental Setup
Experimental Results
Experimental Setup : Beam Contamination 1
78Zn
+ 78Ga + 78Rb
Exp Setup Contam
without n-converter
with n-converter
78Rb
E
78Ga
78Zn
78Zn
DE
78Ga
DE
Ibeam,Zn/Itotal  50%
Coulomb Excitation of Neutron Rich Zn Isotopes
Jarno Van de Walle
Physics Motivation
Experimental Setup
Experimental Results
78Zn
78Ga
Experimental Setup : Beam Contamination 2
= laser ionization
= surface ionization
Exp Setup Contam
1. particle spectrum
laser ON
laser OFF
2. particle count rate (laser ON/OFF)
3. b-decay intensities (laser ON)
Coulomb Excitation of Neutron Rich Zn Isotopes
Jarno Van de Walle
Physics Motivation
Experimental Setup
Experimental Results
Experimental Results : 74Zn
Exp Res 74 (1)
74Zn
beam on 120Sn target
(2.3 mg/cm2 - 2.87 MeV/u)
12.5h ~4E6 parts/sec on target
2+
4+
1418.6(1)
2+
606.01(5)
0+
74Zn
Coulomb Excitation of Neutron Rich Zn Isotopes
Jarno Van de Walle
Physics Motivation
Experimental Setup
Experimental Results
Exp Res
particles
Experimental Results : particle spectrum
beam
Strip Number
76Zn
+ 76Ga
target
120Sn
Coulomb Excitation of Neutron Rich Zn Isotopes
Jarno Van de Walle
Physics Motivation
Experimental Setup
Experimental Results
Experimental Results : 74Zn coulex
Exp Res 74 (2)
74Zn
beam on 120Sn target
(2.3 mg/cm2 - 2.87 MeV/u)
12.5h ~4E6 parts/sec on target
: 2+0+ doppler corrected
Coulomb Excitation of Neutron Rich Zn Isotopes
Jarno Van de Walle
Physics Motivation
Experimental Setup
Experimental Results
Experimental Results : 76Zn coulex
Exp Res 76 (1)
76Zn
beam on 120Sn target
(2.3 mg/cm2 - 2.83 MeV/u)
14.5h ~1.3E6 parts/sec on target
Coulomb Excitation of Neutron Rich Zn Isotopes
Jarno Van de Walle
Physics Motivation
Experimental Setup
Experimental Results
Experimental Results : 76Zn coulex
Exp Res 76 (2)
76Zn
beam on 120Sn target
76Ga
(2.3 mg/cm2 - 2.83 MeV/u)
14.5h ~1.3E6 parts/sec on target
76Zn:
Coulomb Excitation of Neutron Rich Zn Isotopes
2+0+ doppler corrected
Jarno Van de Walle
Physics Motivation
Experimental Setup
Experimental Results
78Zn
Experimental Results : 78Zn coulex
Exp Res 78 (1)
beam on 108Pd target
(2.0 mg/cm2 - 2.86 MeV/u)
23.5h ~3.2E4 parts/sec on target
2+ state in 78Zn: fixed
(8+)
730
891
(6+)
(4+)
2+
0+
78Zn
Coulomb Excitation of Neutron Rich Zn Isotopes
Jarno Van de Walle
Physics Motivation
Experimental Setup
Experimental Results
78Zn
Experimental Results : 78Zn coulex
Exp Res 78 (2)
beam on 108Pd target
(2.0 mg/cm2 - 2.86 MeV/u)
23.5h ~3.2E4 parts/sec on target
doppler corrected
Coulomb Excitation of Neutron Rich Zn Isotopes
Jarno Van de Walle
Physics Motivation
Experimental Setup
Experimental Results
Experimental Results : coulex theory
First order perturbation theory :
Alder & Winther : "Electromagnetic Excitation - Theory of Coulomb Excitation with Heavy Ions"
North-Holland, 1975, Amsterdam
Exp Res theory
N
N


 ,2 0
 ,2 0
Calculate with  B(E2)
dNA
 Miniball,Zn .E2, 74 Zn .
Iin ,Zn
74
Zn
A
dNA
 Miniball,Sn .E2,120 Sn .
Iin,Zn+Ga
120
Sn
A
Laser On/Off
Calculate
E2, 74 Zn 
Miniball,Sn
Miniball,Zn
Coulomb Excitation of Neutron Rich Zn Isotopes
.E2,120 Sn
. N
N
 ,2 0

 ,2 0



Spectrum
74
Zn
120
Sn
x
Iin,Zn
Iin,Zn+Ga
Jarno Van de Walle
Physics Motivation
Experimental Setup
Experimental Results
Experimental Results + Shell Model theory
Exp Res BE2
 : theoretical B(E2)-values
f,p,g - valence space beyond 56Ni core : ANTOINE shell model code
(N. Smirnova - University Gent)
Coulomb Excitation of Neutron Rich Zn Isotopes
Jarno Van de Walle
Physics Motivation
Experimental Setup
Experimental Results
Conclusion + Outlook
Concl
Coulex of 74,76,78Zn :
° fixed 2+ in 78Zn
° preliminary B(E2) values
° systematic errors "understood"
July 2005 :
° 5-8th july : coulex of 68,70Ni (!)
° 13-18th july : coulex of 70Cu isomeres (!)
late 2005
° re-measuring 78Zn + 80Zn
Coulomb Excitation of Neutron Rich Zn Isotopes
Jarno Van de Walle