High-spin states and signature inversion in 78Br.

Abstract

High-spin states in {sup 78}Br have been studied up to an excitation energy of approximately 6 MeV and a spin of 17{h_bar} using the {sup 70}Zn({sup 11}B,3{ital n}){sup 78}Br reaction at a beam energy of 45 MeV. The properties of the observed rotational bands, including moments of inertia, signature splitting, and signature inversion, are discussed within the context of the cranked shell model. It is shown that cranked-shell-model calculations are able to reproduce the experimentally observed signature inversion in the positive-parity yrast bands in the odd-odd isotopes {sup 74,76,78}Br, which permits the assignments of quasiparticle configurations to these bands. {copyright} {ital 1996 The American Physical Society.}