Abstract
High-spin states in have been studied using the Li,4nγ) reaction at 45 MeV. The in-beam techniques employed included relative γ-ray excitation functions, γ-γ coincidences, and γ-ray angular distribution measurements. Low-lying collective bands built on the 1 and 2 quasiproton states show large signature splitting. At higher excitation energies (2.346 and 3.399 MeV), two strong ΔI=1 cascades are also observed with small signature splitting. These latter bands probably arise from three quasiparticle configurations. The one quasiparticle bands are interpreted within the framework of the axially symmetric rotor-plus-particle model with a variable moment of inertia, the generalized particle-asymmetric-rotor model, and the interacting boson-fermion model. High-spin features of are compared with the predictions of the cranked shell model. All of the models indicate that is a soft nucleus which exhibits shape coexistence.
- Received 22 July 1987
DOI:https://doi.org/10.1103/PhysRevC.37.621
©1988 American Physical Society