Abstract
The occurrence of seniority isomers in semimagic nuclei is a clear indication for shell closure. By performing large-scale shell-model calculations in a model space that allows excitations across the neutron and proton shell gaps, we investigate the isomerism along the isotonic chain. The calculation describes well the properties of the experimentally observed isomeric state and the other low-lying states in , and . We further predict energy levels and transitions for and as their structure information is necessary for a complete understanding of the seniority picture. Our results, together with other existing evidence, support the conclusion that the shell closure persists at the neutron number in the neutron-rich region.
- Received 22 April 2014
DOI:https://doi.org/10.1103/PhysRevC.89.064311
©2014 American Physical Society