A Semi-Empirical Formula for Two-Neutrino Double-Beta Decay

TL;DR

This paper introduces a semi-empirical formula for calculating nuclear matrix elements in two-neutrino double-beta decay, improving accuracy and predictive power over previous models by incorporating nuclear properties.

Contribution

The paper presents a novel semi-empirical formula that better matches experimental data and offers reliable predictions for nuclear systems relevant to double-beta decay.

Findings

SEF yields the best agreement with experimental NMEs

The formula is stable and cross-validated

Provides predictions for key nuclear systems

Abstract

We propose a semi-empirical formula (SEF) for calculating the nuclear matrix elements (NMEs) for two-neutrino double-beta decay. The SEF's dependence on the proton and neutron numbers, the pairing, isospin, and deformation properties of the initial and final nuclei is inspired by the insights offered by nuclear many-body methods and trends in experimental data. Compared with the previous phenomenological and nuclear models, the SEF yields the best agreement with the experimental NMEs. Its stability and predictive power are cross-validated, and predictions are provided for nuclear systems of experimental interest.