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The first, to our knowledge, calculation of neutrinoless double beta decay (0νββ-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 0νββ-decay amplitude is taken into account. A detailed nuclear structure study includes the discussion of the sensitivity of the obtained SRQRPA results for 0νββ-decay of 76 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. PACS numbers:23.40. Hc, 21.60.Jz, 27.50.+e, 27.60.+j The neutrino mass and mixing of neutrinos are the main subject of the elementary 1

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The Gamow-Teller matrix elements of 2 nu beta beta transitions to a 21+ final excited state has been calculated within the QRPA formalism for 76Ge and 136Xe. The relative stability of the calculation with respect to the particle-particle interaction strength is confirmed; on the other hand, the results are strongly dependent on the choice of the single-particle energy levels. A plausible explanation of such behaviour, originating in the interference of the individual contributions due to the third power of the energy denominator, has been proposed.