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arXiv · 1910.04146

Short-range correlations for neutrinoless double-beta decay and low-momentum NN potentials

L. Coraggio·N. Itaco·R. Mancino
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Abstract

We approach the calculation of the nuclear matrix element of the neutrinoless double-beta decay process, considering the light-neutrino-exchange channel, by way of the realistic shell-model. In particular the focus of our work is spotted on the role of the short-range correlations, which should be taken into account because of the short-range repulsion of the realistic potentials. Our shell-model wave functions are calculated using an effective Hamiltonian derived from the high-precision CD-Bonn nucleon-nucleon potential, the latter renormalized by way of the so-called V-low-k approach. The renormalization procedure decouples the repulsive high-momentum component of the potential from the low-momentum ones by the introduction of a cutoff Lambda, and is employed to renormalize consistently the two-body neutrino potentials to calculate the nuclear matrix elements of candidates to this decay process in mass interval ranging from A=76 up to A=136. We study the dependence of the decay operator on the choice of the cutoff, and compare our results with other approaches that can be found in present literature.

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L. Coraggio, N. Itaco, R. Mancino. 2019-10-09. Short-range correlations for neutrinoless double-beta decay and low-momentum NN potentials. https://doi.org/10.1088/1742-6596%2F1643%2F1%2F012124

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