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arXiv · 1805.07815

Bound-state double-$β$ decay

A. Babič·D. Štefánik·M. I. Krivoruchenko·F. Šimkovic
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Abstract

We consider new modes of two-neutrino and neutrinoless double-$β$ decays in which one $β$ electron goes over to a continuous spectrum and the other occupies a vacant bound level of the daughter ion. We calculate the corresponding phase-space factors of the final states, estimate the partial decay rates, and derive the one- and two-electron energy spectra using relativistic many-electron wave functions of atoms provided by the multiconfiguration Dirac-Hartree-Fock package GRASP2K. While the bound-state neutrinoless double-$β$ decays are strongly suppressed, their two-neutrino counterparts can be observed in the next-generation double-$β$-decay experiments, most notably SuperNEMO.

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A. Babič, D. Štefánik, M. I. Krivoruchenko, F. Šimkovic. 2018-11-24. Bound-state double-$β$ decay. https://doi.org/10.1103/physrevc.98.065501

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