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19/2 + Isomer of 125 Cd Gary Simpson LPSC Grenoble. Experimental technique Shell-Model Interpretation. Question of changes in N-N interaction in 132 Sn region. Low Q b value and high 1 + state in 130 In. A. Scherillo et al . Phys. Rev. C 70, 054318 (2004). Dillmann et al.
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19/2+ Isomer of 125Cd Gary Simpson LPSC Grenoble • Experimental technique • Shell-Model Interpretation
Question of changes in N-N interaction in 132Sn region Low Qb value and high 1+ state in 130In
A. Scherillo et al. Phys. Rev. C 70, 054318 (2004) Dillmann et al. Napoli interactions
Also data from Hellstrom et al. Hirschegg (2003) No level scheme
The Lohengrin Fission-Product Spectrometer Flight time 1-2 s -can use isomers Separates according to A/q and E/q No ion source - no chemical selectivity ~2×1012 fissions/s (3.5 mg of 239Pu 742 b) A/A~250 Solid angle < 2 x 10-5 Rates at focal point ~ 3000 ions of 132Sn /s
Experimental Setup • Gamma detection efficiency ~4 % at 1 MeV and ~20 % at 100 keV 1 Miniball triple cluster + l Clover detector
Shell-Model Interpretation • Napoli Interactions • CD-Bonn N-N potential, Vlow-k renormalization • Model Space Z=28-50 N=50-82 p g9/2 p1/2 p3/2 f5/2 • h11/2 s1/2 d3/2 d5/2 g7/2 No truncation Calculations performed with NuShellX code (Use 8 processors and ~16 Gb of memory!)
Yrast states 19/2+ spin trap
Data compare very well with shell-model calculations T1/2 theo~40 ms Strongest component of 19/2+ isomer is pg9/2-2nd3/2-1
Conclusions • Napoli interactions work well for most Cd nuclei where data exist and calculations are feasible • 2+ states are 200 keV too high (400 keV 128Cd) • No modifications needed to interaction • New partial level scheme for 125Cd Thanks for making the interactions available Thanks to the theorists who provide and maintain shell model codes (NuShellX, Antoine) Access to these interactions has given me ideas for two proposals
Collaborators J.A. Pinston, J. Genevey LPSC R. Orlandi, A. Scherillo, I. Tsekhanovich ILL N. Warr Cologne • Covello, A. Gargano Napoli