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arXiv · 2604.22727

Ab initio short-range nuclear matrix elements for neutrinoless double-beta decay

A. Todd·T. Shickele·A. Belley·L. Jokiniemi·J. D. Holt
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Abstract

We present converged ab initio calculations of short-range neutrinoless double-beta ($0\nu\beta\beta$) decay nuclear matrix elements for the key experimental isotopes $^{76}$Ge, $^{82}$Se, $^{130}$Te and $^{136}$Xe. Starting from different nuclear forces derived from chiral effective field theory, we apply the in-medium similarity renormalization group to obtain an effective valence-space Hamiltonian along with consistently transformed $0\nu\beta\beta$-decay operators. We then obtain a range of values for the matrix elements that is consistent with, but generally smaller than, those from phenomenology. Finally, we combine our results with current limits from $0\nu\beta\beta$-decay searches to obtain constraints for the sterile-neutrino mixing-mass parameter space when considering the inclusion of a fourth, sterile neutrino.

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A. Todd, T. Shickele, A. Belley, L. Jokiniemi, J. D. Holt. 2026-04-24. Ab initio short-range nuclear matrix elements for neutrinoless double-beta decay. https://doi.org/10.1103/d2n7-n2c7

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