Nuclear transition matrix elements for neutrinoless double-β decay of 76Ge within mechanisms involving sterile neutrinos, majorons and composite neutrinos

Abstract

Using HFB wave functions generated with a realistic KUO and an empirical JUNE45 effective two-body interactions, nuclear transition matrix elements (NTMEs) M(K) for the 0+ → 0+ transition of neutrinoless double-β decay of 76Ge isotope are calculated within mechanisms involving sterile neutrinos, Majorons and compositeness scenario. Uncertainties in nuclear transition matrix elements are estimated by calculating sets of 12 NTMEs with these two sets of wave functions, two alternative forms of finite size effects (FNS) and three different parametrizations of short range correlations (SRC). Uncertainties in NTMEs within mechanisms involving sterile neutrinos, Majorons and composite neutrinos turn out to be about 10%-36% depending on the mass of sterile neutrinos, 10% and 37%, respectively.