2017 Impact factor 2.799
Hadrons and Nuclei
Eur. Phys. J. A 9, 191-195

New high-spin microsecond isomers in 131Sb

J. Genevey1 - J.A. Pinston1 - H. Faust2 - C. Foin1 - S. Oberstedt2 - M. Rejmund3

1 Institut des Sciences Nucléaires, IN2P3-CNRS/Université Joseph Fourier, F-38026, Grenoble Cedex, France
2 Institut Laue-Langevin, F-38042 Grenoble Cedex, France
3 DAPNIA/SPhN, CEA Saclay, F-91191 Gif-sur-Yvette Cedex, France
genevey@isn.in2p3.fr

Received: 7 June 2000 / Revised version: 5 September 2000
Communicated by J. Äystö

Abstract
In this work we have identified and studied the decay of two new microsecond isomers 19/2- and 23/2+ in 131Sb. This neutron-rich nucleus was produced by thermal neutron-induced fission of 241Pu. The detection is based on time correlation between fission fragments selected by the LOHENGRIN spectrometer at ILL (Grenoble) and the $\gamma$-rays or conversion electrons from isomers. These new data on high-spin states complete the level scheme previously obtained from $\beta$-decay. A large fraction of the members of the $\pi g_{7/2} \nu (h_{11/2}^{-1} d_{3/2}^{-1})$ and $\pi g_{7/2} \nu h_{11/2}^{-2}$ multiplets are now known and were compared with a multi-particle shell model calculation.

PACS
23.20.Lv Gamma transition level energies - 25.85.Ec Neutron-induced fission - 21.60.Cs Shell model - 27.60.+j 90$\le$A$\le$149


Copyright Società Italiana di Fisica, Springer-Verlag 2000