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arXiv · 2210.05809

Constraining Neutrinoless Double-Beta Decay Matrix Elements from Ab Initio Nuclear Theory

A. Belley·T. Miyagi·S. R. Stroberg·J. D. Holt
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Abstract

As experimental searches for neutrinoless double-beta ($0\nu\beta\beta$) decay are entering a new generation, with hopes to completely probe the inverted mass hierarchy, the need for reliable nuclear matrix elements, which govern the rate of this decay, is stronger than ever. Since a large discrepancy in results is typically found with nuclear modela, a large unknown still exists on the sensitivity of these experiments to the effective neutrino mass. We consider this problem from a first-principles perspective, using the ab initio valence-space in medium similarity renormalization group. In particular, we study correlations of the $0\nu\beta\beta$-decay matrix elements in $^{76}$Ge with other observables, such as the double Gamow-Teller giant resonance, from 34 input chiral interactions in an attempt to constrain our uncertainties and investigate the interaction dependence of the nuclear matrix element.

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A. Belley, T. Miyagi, S. R. Stroberg, J. D. Holt. 2022-10-11. Constraining Neutrinoless Double-Beta Decay Matrix Elements from Ab Initio Nuclear Theory. https://doi.org/10.1063/5.0249855

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