Neutrinoless double beta decay matrix elements in light nuclei

TL;DR

This paper presents the first ab initio calculations of neutrinoless double beta decay matrix elements in light nuclei, providing benchmarks for future many-body methods applicable to heavy nuclei.

Contribution

It introduces novel ab initio calculations of decay matrix elements in light nuclei using Variational Monte Carlo methods with realistic nuclear interactions.

Findings

Benchmark results for light nuclei matrix elements

Impact of short-range correlations on decay operators

Comparison of different transition operator forms

Abstract

We present the first ab initio calculations of neutrinoless double beta decay matrix elements in $A=6$-$12$ nuclei using Variational Monte Carlo wave functions obtained from the Argonne $v_{18}$ two-nucleon potential and Illinois-7 three-nucleon interaction. We study both light Majorana neutrino exchange and potentials arising from a large class of multi-TeV mechanisms of lepton number violation. Our results provide benchmarks to be used in testing many-body methods that can be extended to the heavy nuclei of experimental interest. In light nuclei we have also studied the impact of two-body short range correlations and the use of different forms for the transition operators, such as those corresponding to different orders in chiral effective theory.