title: Collective oblate rotation at high spins in neutron-rich 180Hf.
abstract: We report on experimental evidence for collective oblate rotation becoming favored at high spins in a rigid, well-deformed, axially symmetric nucleus. Excited states established up to spin 20variant Planck's over 2pi in 180Hf are consistent with predictions that nucleon alignments would favor oblate over prolate shapes at high spins in neutron-rich Hf isotopes. The results highlight the influence of valence orbitals on the interplay between nucleon alignments and nuclear shapes and provide a rare example of independent particle dynamics in competing potential wells.
authors.affiliation: Department of Physics, University of Massachusetts Lowell, Lowell, Massachusetts 01854, USA.
authors.forename: U S
authors.initials: US
authors.lastname: Tandel
authors.forename: S K
authors.initials: SK
authors.lastname: Tandel
authors.forename: P
authors.initials: P
authors.lastname: Chowdhury
authors.forename: D
authors.initials: D
authors.lastname: Cline
authors.forename: C Y
authors.initials: CY
authors.lastname: Wu
authors.forename: M P
authors.initials: MP
authors.lastname: Carpenter
authors.forename: R V F
authors.initials: RV
authors.lastname: Janssens
authors.forename: T L
authors.initials: TL
authors.lastname: Khoo
authors.forename: T
authors.initials: T
authors.lastname: Lauritsen
authors.forename: C J
authors.initials: CJ
authors.lastname: Lister
authors.forename: D
authors.initials: D
authors.lastname: Seweryniak
authors.forename: S
authors.initials: S
authors.lastname: Zhu