Neutrinoless double β decay within the self-consistent renormalized quasiparticle random phase approximation and inclusion of induced nucleon currents

The first calculation (to our knowledge) of neutrinoless double beta decay $(0\ensuremath{\nu}\ensuremath{\beta}\ensuremath{\beta}$-decay) matrix elements within the self-consistent renormalized quasiparticle random phase approximation (SRQRPA) is presented. The contribution from the momentum-dependent induced nucleon currents to $0\ensuremath{\nu}\ensuremath{\beta}\ensuremath{\beta}$-decay amplitude is taken into account. A detailed nuclear structure study includes the discussion of the sensitivity of the obtained SRQRPA results for $0\ensuremath{\nu}\ensuremath{\beta}\ensuremath{\beta}$ decay of ${}^{76}\mathrm{Ge}$ to the parameters of nuclear Hamiltonian, two-nucleon short-range correlations, and the truncation of the model space. A comparison with the standard and renormalized QRPA results is presented. We have found a considerable reduction of the SRQRPA nuclear matrix elements, resulting in less stringent limits for the effective neutrino mass.