Projected shell model for Gamow-Teller transitions in heavy, deformed nuclei

¹ Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
² Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai 200240, China
³ China Institute of Atomic Energy, P.O. Box 275(18), Beijing 102413, China
⁴ State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190, China

^a e-mail: sunyang@sjtu.edu.cn

Published online: 12 February 2016

Abstract

Calculations of Gamow-Teller (GT) transition rates for heavy, deformed nuclei, which are useful input for nuclear astrophysics studies, are usually done with the quasiparticle random-phase approximation. We propose a shell-model method by applying the Projected Shell Model (PSM) based on deformed bases. With this method, it is possible to perform a state-by-state calculation for nuclear matrix elements for β-decay and electron-capture in heavy nuclei. Taking β⁻ decay from ¹⁶⁸Dy to ¹⁶⁸Ho as an example, we show that the known experimental B(GT) from the ground state of the mother nucleus to the low-lying states of the daughter nucleus could be well described. Moreover, strong transitions to high-lying states are predicted to occur, which may considerably enhance the total decay rates once these nuclei are exposed to hot stellar environments.