Study of the double Gamow-Teller transitions using the shell model approach

TL;DR

This paper investigates double Gamow-Teller transitions in calcium isotopes using the nuclear shell model, providing insights into the transition strengths relevant for double beta decay.

Contribution

It applies the shell model to calculate double Gamow-Teller strength distributions, offering a detailed analysis of transition probabilities in light double beta-decay candidates.

Findings

Double Gamow-Teller strength distributions are calculated for $^{48}$Ca and $^{46}$Ca.

The nuclear matrix element for the double beta decay transition is a small fraction of the total transition.

The shell model approach provides detailed insights into the transition mechanisms.

Abstract

The double Gamow-Teller strength distributions in the lightest double beta-decay candidate $^{48}$Ca and its isotope $^{46}$Ca were calculated using the nuclear shell model by applying the single Gamow-Teller operator two times sequentially on the ground state of parent nucleus. The nuclear matrix element of the double Gamow-Teller transition from the ground state to the ground state that goes into the double beta decay calculation was shown as a small fraction of the total transition.