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arXiv · 1909.06501

Benchmark neutrinoless double-beta decay matrix elements in a light nucleus

R. A. M. Basili·J. M. Yao·J. Engel·H. Hergert·M. Lockner·P. Maris·J. P. Vary
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Abstract

We compute nuclear matrix elements of neutrinoless double-beta decay mediated by light Majorana-neutrino exchange in the A = 6 system. The goal is to benchmark two many-body approaches, the No-Core Shell Model and the Multi-Reference In-Medium Similarity Renormalization Group. We use the SRG-evolved chiral N3LO-EM500 potential for the nuclear interaction, and make the approximation that isospin is conserved. We compare the results of the two approaches as a function of the cutoff on the many-body basis space. Although differences are seen in the predicted nuclear radii, the ground-state energies and neutrinoless double-beta decay matrix elements produced by the two approaches show significant agreement. We discuss the implications for calculations in heavier nuclei.

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R. A. M. Basili, J. M. Yao, J. Engel, H. Hergert, M. Lockner, P. Maris, J. P. Vary. 2020-05-07. Benchmark neutrinoless double-beta decay matrix elements in a light nucleus. https://doi.org/10.1103/physrevc.102.014302

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