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Relativistic Coulomb excitation of nuclei Relativistic Coulomb excitation of nuclei near near 100100SnSnC.Fahlander, J. Eckman, M. Mineva, D. Rudolph, Dept. Phys., Lund University, Sweden
M.G., A.Banu, A. Blazhev, H.Grawe, T.R.Saito, et al., GSI, Darmstadt, Germany
J.Nyberg, et al., Dept. Rad. Sci., Uppsala University, Sweden
B.Cederwall, et al., RIT, Stockholm, Sweden
M.Bentley et al., Dept. Phys., Keele University, UK
G.de Angelis, A. Gadea et al., LNL, Padova, Italy
M.Palacz, et al., HIL, Warsaw University, Poland
D.Sohler, et al., INR, Debrecen, Hungary
P.Nolan, et al., Liverpool University, UK Surrey 29-30 March, 2004 RISING STOPPED BEAM PHYSICS WORKSHOP
100100Sn region studied with relativistic beamsSn region studied with relativistic beams
B(E2: 2+ → 0+) structure of isomers
Experimental conditions
Fusion symmetric reaction
EUROBALL, GASP + Ancillaries
MSEP β decay
Fragmentation Coulex
Isomers β decay → T. F. talk
Physics interest
• Shell structureSPE
• Residual Interaction E2 correlations
• Shell gap
• Core excitation:E2E3
• Magnetic rotationM1 bands
E3E2 E2
I, E
ExperimentalExperimental DetailsDetails
Primary beam: 124124Xe, 700 AMeVXe, 700 AMeV
Production target: 99Be, 4 g/cmBe, 4 g/cm22
Coulex target: 197197Au, 0.4 g/cmAu, 0.4 g/cm22
Nuclei of interest: 108108Sn (58h),Sn (58h),112112Sn(28h), ~150 AMeVSn(28h), ~150 AMeV ~ 3-5 kHz intensity~ 3-5 kHz intensity
Fragment identificationFragment identification
projectile
target
outgoing
A/Q
Z
108Sn
before the target (FRS)before the target (FRS)
Z
A/Q
Analysis in progress...
Simulated experimental spectrawith realistic 108Sn beam intensity and background
including 2+ lifetime effects and estimated cross section
Energy [keV]
Cou
nts
Next step after succesful analysis, 106Sn, 104Sn (new proposal)
pessimistic expected
56Ni and 100Sn similarities
12+:76Ni
8+:130Cd
54Fe
A. Blazhev et al., PRC submittedGDS: F.Nowacki, Nuc. Phys. A 704 (2002) 223cESM: H. Grawe et al., NS98 AIP CP 481 (1999) 177
Core excited states in 98Cd
eπ = 1.3(2) eπ = 1.1
Shell Model calculations GDS
100Sn shell gap:
12+: πg9/2-2νg9/2
-1(d5/2,g7/2)
dominated by strong binding
πg9/2-2νg9/2
-1 ≈ πg9/2-2
E(12+)-E(8+) – measure of the shell gap
EXP – SM = -325 keV for ESM (6.78 MeV)6.46 MeV
-34 keV for GSD (6.5 MeV)6.47 MeV
Esg = 6.46(15) MeV
Outlook:
E2 correlation Coulex SPE structure and residual interaction isomers-stopped beam
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