Unified-model calculations for 139Ce

Abstract

The energy spectrum of the odd-neutron nucleus 139Ce is described in a unified model in intermediate coupling. The coupling strength between phonon excitations and the neutron single-hole motion, the single-hole energies are taken as free parameters and are determined in a least-squares fitting procedure. The wave functions are used to calculate M1 and E2 moments and transition probabilities. The lifetime of the isomeric I π = 11 − 2 level is reproduced in the model. Also spectroscopic factors for the reaction 140 Ce( 3 He, α) 139 Ce are calculated.