Transcript Slide 1

Helsinki 17 September 2007
Highlights of physics
from current facilities
Results from EURONS-supported projects
carried out at the TNA facilities
TNA 01
GSI
Darmstadt
130Cd
82
: N = 82 shell quenching or not
GSI
Support from earlier 130Cd82 data
- New
130Cd
Data -
from the FRS@GSI on a stopper inside 15 EUROBALL clusters
A. Jungclaus et al., PRL, in press
No N = 82 shell quenching in 130Cd !
Pygmy-Dipole Strength - Neutron-Skin Thickness and Asymmetry
GSI
Photoabsorption
124Sn
Secondary beam 132,130...Sn
Coulomb excitation
at 500 MeV/u
130Sn
132Sn
Neutron-skin thickness
Properties of Neutron Stars
δrn-Rp
R
LAND collaboration
A.
Klimkiewicz et al., subm. to PRL (2007);
B. P. Adrich et al., PRL 95 (2005)
TNA 2
UCL
Louvain-la-Neuve
Breakout from the hot CNO
cycle:18Ne(a,p)21Na
reaction
Discrepancy in the earlier
Cross-section measurements
New thin- 4He target measurements by employing
LEDA and 18Ne radioactive beams
Examined reaction protons at two energies, ECM = 1.7 MeV and ECM = 2.5 MeV
ECM = 1.7 MeV,
typical beam intensity ~1.5 x 106 pps,
data taken over 52.4 hours
**
**Josephides
ECM = 2.5 MeV,
typical beam intensity ~4.5 x 105 pps,
data taken over 75.6 hours
**
et al, Edinburgh University and CRC Louvain-la-Neuve
UCL
Destruction of 18F in Nova via 18F(p,α) reactions
19Ne
UCL
states near the 18F + p threshold studied via 15O(α,α’)
•
Radioactive 15O (intensity ~ 9.3 x 106 pps) beam on a thick 4He gas target
•
Energy range of ECM between 2.0 – 3.2 MeV
Data shown is of energy range 2.2 – 3.2 MeV
R-Matrix calculation based on nominal values
(D.W.Bardayan et al., Phys. Rev. C70 (2004)
015804)
• Experimental data shows similar resonance structure to the R-Matrix calculation within
energy region studied. A detailed analysis is currently in progress
** Josephides et al, experiment conducted at CRC Louvain-La-Neuve by an Edinburgh University, CRC IPN, Orsay and The University of York collaboration
TNA 3
GANIL
Caen
GANIL
N = 28 shell closure in 42Si28 ?
Expérimental procedure
48Ca
(>1012 pps)  cocktail beam around 44S  Si isotopes +
g
Château de Crystal (e~30%)
44S
Secondary beams
SPEG (e~100%)
SISSI
 44S
2+  0+ : 770 ± 19 keV
2+ energy (MeV)
48Ca
 42Si
4
3
Ca
S
Si
2
1
0
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
42Si
is a first nucleus
of a second Isle of inversion
neutron number N
B. Bastin et al. Phys.Rev.Lett. 99, 022503 (2007)
New pathways to bypass the 15O waiting point
Resonant Elastic Scattering
H(15O,p)15O
107 pps
E = 1.2 A MeV
Resolution = 4 keV
R-matrix analysis
New astroreactions
g.s.
16F
GANIL
TNA 4
JYFL
Jyväskylä
K – isomers in 254No
JYFL
208Pb(48Ca,2n)254No
JUROGAM
GREAT
RITU
JYFL
High-accuracy mass measurements at JYFLTRAP
~200 precise atomic masses of ground and isomeric states.
15
20
25
30
35
40
45
50
55
60
65
70
75
80
55
50
50
45
45
40
40
35
35
30
30
25
25
20
20
15
15
Z
55
10
Testing of the hypotesis of conserved
vector current:
Sub-keV precision on QEC-values
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
for superallowed beta decay.
N
Evolution of N=50 shell gap.
Hardy&Towner, PRC71(-05)055501
JYFLTRAP
CPT, Argonne
ISOLTRAP, CERN
3095
N=46
N=48
N=50
N=52
N=54
26
24
22
S2n (MeV)
Comparative half-life [s]
28
20
18
16
14
12
10
8
3090
3085
3080
3075
3070
3065
10
3060
6
28
30
32
34
36
38
Z
40
42
44
46
22
C
Al
O
5
10
38
Cl
26
14
48
34
Mg
m
15
m
34
Ar
54
46
K
42
Sc
20
74
Co
V
50
Mn
Rb
62
25
Z of the daughter nucleus
Ga
30
35
TNA 5
LNL
Legnaro
LNL
Shell closure evolution around N=50
IRES-IPHC Strasbourg, University of Paisley,
University of Istanbul, IPNO Orsay, GANIL,
Ruder Bošković Institute, INRNE Sofia, INFN
82Se+238U @ E = 505 MeV
78Ni+3p
4+
N=50
+4p
+5p
Fission
QE
Ge
The N = 50 shell-gap survives
82Ge
s ~ 0.6 mb
Static quadrupole moments for coexisting isomeric
states in neutron deficient Pb nuclei
12+ 2 n state (spherical)
LNL
11- 2 p particle – 2p hole state (deformed)
NIPNE Bucharest, University of Bonn, IKS – University of Leuven, INRNE and University of Sofia, INFN
28Si+168Er
and 29Si+170Er @ E = 143 MeV
TDPAD spectra
Er target on a polycrystalline lattice of Bi
Time-Differential Perturbed Angular
Distribution
TDPAD method
Measured for the first time
Remeasured with an increased precision
This can be viewed as evidence for shape mixing
Average deformation  2 = – 0.146(14)
TNA 7
KVI
Groningen
GT – matrix elements for the 64Zn - (64Cu) – 64Ni double β - decay KVI
AGOR Cyclotron + BIG BITE Spectrometer + EuroSuperNova detector system
KVI
TNA 8
ISOLDE
CERN
Post-accelerated isomeric beams!
Optional
stripper
REX-Isolde
7-GAP
9-GAP
RESONATOR RESONATORS
@ 202.56 MHz @ 101.28 MHz
Experiments
MASS
SEPARATOR
3.0
MeV/u
2.2
MeV/u
IH
ISOLDE
RFQ
Rebuncher
ISOLDE
beam
0.3
MeV/u
60
keV
REXTRAP
1.2
MeV/u
ISOLDE
REXEBIS
Primary
High energy
target
driver beam
protons
MINIBALL Ge - Array
68Cu
Coulex
61+
I Stefanescu et al, PRL 98 (2007) 122701
Parity non-conservation in nuclei: 8+ and 8- states in 180Hf
ISOLDE
Mass separated 180mHf polarized on a Fe foil at 7 mK
NICOLE
r
 B up
E2/M2 mixing ratio of the 501 keV transition
- 0.0324(16)
In agreement with the earlier value of
- 0.030(2) , measured 30 years ago !
Anisotropy of the highly K- forbidden 501 keV
transition relative to 444 keV
for B-field alternatively up
J.R. Stone et al,
and down
PR C76 (2007) 025502
Helsinki 17 September 2007
Analysis of large amount of data in progress
→ more highlights in the coming years