New insights into neutron-rich nuclei at high spin

With new high statistic data, new isotopes and new high-spin structures axe observed in neutron-rich nuclei populated in the spontaneous fission of Cf-252. The Te-135 levels are extended, and many new levels in Ba-139,Ba-141 observed. The coexistence of collective and single particle-hole states is found in Te-135. The N = 83 Te-135 and Ba-139 show marked differences associated with differences in their particle and hole states. New levels in Ba-141 complete evidence for two opposite-parity doublets characteristic of stable octupole deformation. In Pd-114,Pd-116 a second backbend is observed for the first time in this mass region and the backbend in Pd-118 occurs earlier than in Pd112-116 because of a reduction in pairing. Gamma-type vibrational bands are seen up to 13(+) to 15(+) in Mo-104,Mo-106, Ru108-112, and Pd112-116. Their behavior reflects prolate to triaxial shapes in these nuclei. The levels of Gd-162,Gd-164 are observed for the first time. As N increases toward mid-shell at 104, the moments of inertia in N = 100 Gd-164 show an unexpected decrease compared to N = 98 Gd-162. The levels in Gd-162,Gd-164 form remarkable shifted identical bands with nuclei separated by 2n, 2p, alpha, and 2alpha.