Higher forbidden unique $\beta^-$ decay transitions and shell-model interpretation

TL;DR

This paper predicts half-lives for higher forbidden unique beta-minus decays in nuclei with mass numbers 40-138 using shell-model calculations, providing insights for future experimental measurements.

Contribution

It introduces shell-model predictions for half-lives of higher forbidden beta-minus decays across a wide mass range, comparing with pnQRPA results.

Findings

Shell-model calculations provide half-life estimates for nuclei where experimental data is scarce.

Comparison between shell-model and pnQRPA results highlights differences and agreements.

Results can guide future experimental efforts to measure these rare decay modes.

Abstract

In the present work, we have predicted the half-lives for the $\beta^{-}$ decay for higher forbidden unique transitions in the mass range of nuclei from A = 40-138. For these transitions, the experimental data for half-lives are not available except for a few cases. The calculations for half-lives are performed within the framework of the nuclear shell model (SM). We have used the effective interactions sdpf-mu, gxpf1a, gwbxg, G-matrix, snet, sn100pn, and jj56pnb to perform the SM calculations in different mass regions. A comprehensive discussion has been made between the SM-predicted half-lives and the scaled half-lives from proton-neutron quasiparticle random-phase approximation (pnQRPA). The results of the present study will be useful to plan new experiments to measure half-lives for these higher forbidden unique $\beta^{-}$ transitions.