THE QRPA STUDY OF NEUTRINOLESS DOUBLE-BETA DECAY WITH AND WITHOUT PROTON-NEUTRON PAIRING

We have examined the role of proton-neutron pairing on the Quasipartic le Random Phase Approximation (QRPA) by calculating neutrinoless doubl e beta decay matrix elements using the recently proposed full-QRPA, wh ich includes proton-neutron pairing. With this full-QRPA we have perfo rmed calculations on the neutrinoless double beta decay matrix element s of the experimentally interesting nuclei A=48, 76, 82, 96, 100, 116, 128, 130 and 136. Using the best presently available experimental lim its on the half-time of neutrinoless double beta decay we have extract ed new limits on the lepton number violating parameters. We have found that the inclusion of proton-neutron pairing makes the limits on the lepton number non-conserving parameters less stringent.