Experimentally determined level densities of the transitional isotopes Sm148,149,150,152 at excitation energies below and around the neutron binding energy are compared with microcanonical calculations based on a Monte Carlo approach to noncollective level densities, folded with a collective enhancement estimated in the frame of the interacting boson model (IBM). The IBM parameters are adjusted so as to reproduce the low-lying discrete levels of both parities, with the exception of the odd-mass nucleus, Sm149, where complete decoupling of the unpaired neutron from the core is assumed. © 2005 The American Physical Society.
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics