Abstract
Several rotational bands have been populated to high spin in the γ-soft nucleus . We present expreimental evidence for a collective oblate rotational band based on a π⊗(ν three-quasiparticle configuration. It is the rotational alignment of the pair of neutrons from the upper midshell which drives the nucleus from a prolate (γ=0°) shape to a collectively rotating oblate (γ=-60°) shape. This band coexists with a prolate band that contains a pair of aligned protons from the lower midshell.
- Received 3 December 1986
DOI:https://doi.org/10.1103/PhysRevLett.58.984
©1987 American Physical Society