Microscopic Structure of the Yrast Bands in Even Xe Isotopes

Abstract: The interaction between collective states consisting mainly of the lowest-energy quadrupole phonons is considered along with that of noncollective states, including high-spin phonons in even Xe isotopes. Calculations are performed for yrast states with spins of up to I π = 18 >+ in the boson approximation. Collective states are gradually substituted for noncollective ones in isotopes with A ≤ 120, leading to a smooth change in values of B(E2) as spin increases. In contrast, there is a sharp transition from the collective to the noncollective band in isotopes with A ≥ 122: the bands intersect and the corresponding B(E2) value falls substantially. © 2018, Allerton Press, Inc.