Projected shell model study of the yrast bands of neutron-deficient Ce126-130 isotopes

摘要

The yrast bands of neutron- deficient Ce126-130 nuclei are studied by using the projected shell model approach. Energy levels, moments of inertia and B(E2) transition probabilities are calculated and compared with the available experimental data. The first and second backbending in Ce-128,Ce-130 are investigated. The question as to why the backbending becomes sharp as the neutron number increases in cerium isotopes is addressed. It turns out that the first backbending is caused by a proton pair and the second backbending in Ce-128,Ce-130 is due to a simultaneous proton and neutron pair breaking.