Extended triaxial projected shell model approach for odd-neutron nuclei

TL;DR

This paper extends the triaxial projected shell model to include multi-quasiparticle configurations, enabling detailed analysis of high-spin states and band crossings in odd-neutron nuclei, specifically odd-mass Xe isotopes.

Contribution

The extension to include three- and five-quasiparticle configurations allows for comprehensive investigation of high-spin phenomena and band crossing behaviors in odd-neutron nuclei.

Findings

Character of band crossing varies with shell filling of 1h11/2 orbital.

Three-quasiparticle states cross the ground state and γ band at different spins.

The model explains signature inversion in γ bands of certain isotopes.

Abstract

In an effort to elucidate the rich band structures observed in odd-neutron systems, triaxial projected shell model approach is extended to include three-quasineutron and five-quasiparticle configurations. This extension makes it possible to investigate the high-spin states up to and including the second band crossing. Detailed investigation has been performed for odd-mass Xe isotopes with the extended basis, and it is shown that character of the band crossing along the yrast line changes with shell filling of the 1h11/2 orbital. Further, it is observed that the three-quasiparticle state that crosses the ground-state configuration, leading to the normal band crossing phenomenon along the yrast line, first crosses the {\gamma} band based on the ground-state configuration at an earlier spin value. This crossing feature explains the occurrence of the signature inversion observed in the {\gamma} bands for some of the studied isotopes.