Beta-decay study within multi-reference density functional theory and beyond

TL;DR

This paper introduces a novel multi-reference density functional theory approach to study beta-decay, successfully applying it to mirror nuclei and achieving results consistent with shell-model predictions, thus supporting two-body current theories.

Contribution

It presents a pioneering no-core-configuration-interaction method within multi-reference density functional theory for beta-decay analysis, extending its application to sd- and pf-shell nuclei.

Findings

Good agreement with shell-model predictions for Gamow-Teller and Fermi matrix elements

Supports two-body current scenarios for axial-vector coupling quenching

Validates the new method as a reliable alternative to traditional models

Abstract

Pioneering study of Gamow-Teller (GT) and Fermi matrix elements (MEs) using no-core-configuration-interaction formalism rooted in multi-reference density functional theory is presented. After successful test performed for 6He -> 6Li beta-decay, the model is applied to compute MEs in the sd- and pf-shell T=1/2 mirror nuclei. The calculated GT MEs and the isospin-symmetry-breaking corrections to the Fermi branch are found to be in a very good agreement with shell-model predictions in spite of fundamental differences between these models concerning model space, treatment of correlations or inclusion of a core. This result indirectly supports the two-body current based scenarios behind the quenching of axial-vector coupling constant.