Octupole shapes and shape changes at high spins in the<i>Z</i>≊58,<i>N</i>≊88 nuclei

Abstract

The shapes of rotating Xe, Ba, Ce, Nd, and Sm nuclei (84\ensuremath{\le}N\ensuremath{\le}94) are calculated using the cranking model with the Woods-Saxon average potential and pairing. The lightest isotopes of Xe and Ba have nearly spherical ground states, but develop octupole and quadrupole deformations under rotation which remain up to very high spins. The ground states of the heavier isotopes have octupole and quadrupole deformations which persist up to medium spins (I\ensuremath{\approxeq}12\ensuremath{\Elzxh}). At higher spins, a shape transition is predicted to reflection-symmetric aligned many-quasiparticle configurations.