Nuclear muon capture as a powerful probe of double-beta decays in light nuclei

Abstract

Ordinary muon-capture (OMC) transitions to the intermediate 1+ states in the two-neutrino double-beta (2νββ) decays of 36Ar, 46Ca, 48Ca and 50Cr have been studied in the framework of the nuclear shell model to probe the structure of these states. Well-established, fitted two-body interaction matrix elements have been used in the study. A significant dependence of these two nuclear processes on the structure of few low-lying intermediate states is found for the A = 36, A = 46 and A = 48 cases. This makes the OMC as a powerful probe of the bulk of the 2νββ nuclear matrix elements for the decays of 36Ar, 46Ca and 48Ca.