β-decay half-lives of neutron-rich N=82,81 isotones by shell-model calculations

Noritaka Shimizu,Tomoaki Togashi,Yutaka Utsuno,W Liu,X Tang,S Zeng,B Guo,Y Wang

doi:10.1051/epjconf/202226011049

Abstract

We perform large-scale shell-model calculations and successfully describe the low-lying spectra and half-lives of neutron-rich N = 82 and N = 81 isotones with Z = 42 − 49 in a unified way. Shell-model study shows that their Gamow-Teller strength distribution has a peak in the low-excitation energies, which significantly contributes to the half-lives. This peak is dominated by the ν0g7/2 → π0g9/2 transition and enhanced on the proton deficient side of these isotones due to the Pauli blocking effect and the change of the effective single-particle energy of the ν0g7/2 orbit.

Highlights

1 Introduction β-decay half-lives of neutron-rich nuclei around N = 82 are key data to understand the second peak of the solar abundance in the r-process nucleosynthesis [1]
We perform large-scale shell-model calculations and successfully describe the low-lying spectra and half-lives of neutron-rich N = 82 and N = 81 isotones with Z = 42 − 49 in a unified way
We performed 250 Lanczos iterations and evaluate the strength distribution in the subspace spanned by the Lanczos vectors

Summary

Introduction

1 Introduction β-decay half-lives of neutron-rich nuclei around N = 82 are key data to understand the second peak of the solar abundance in the r-process nucleosynthesis [1]. We adopt nuclear shell-model calculations and investigate theoretically the β-decay properties of N = 82 and N = 81 isotones.

Results

Conclusion