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arXiv · 0710.2055

Anatomy of nuclear matrix elements for neutrinoless double-beta decay

Fedor Simkovic·Amand Faessler·Vadim Rodin·Petr Vogel·Jonathan Engel
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Abstract

We show that, within the Quasiparticle Random Phase Approximation (QRPA) and the renormalized QRPA (RQRPA) based on the Bonn CD nucleon-nucleon interaction, the competition between the pairing and the neutron-proton particle-particle and particle-hole interactions causes contributions to the neutrinoless double-beta decay matrix element to nearly vanish at internucleon distances of more than 2 or 3 fermis. As a result, the matrix element is more sensitive to short-range/high-momentum physics than one naively expects. We analyze various ways of treating that physics and quantify the uncertainty it produces in the matrix elements, with three different treatments of short-range correlations.

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Fedor Simkovic, Amand Faessler, Vadim Rodin, Petr Vogel, Jonathan Engel. 2008-04-02. Anatomy of nuclear matrix elements for neutrinoless double-beta decay. https://doi.org/10.1103/physrevc.77.045503

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