Energy Density Functional Study of Nuclear Matrix Elements for Neutrinoless ββ Decay

We present an extensive study of nuclear matrix elements (NME) for the neutrinoless double-beta decay of the nuclei (48)Ca, (76)Ge, (82)Se, (96)Zr, (100)Mo, (116)Cd, (124)Sn, (128)Te, (130)Te, (136)Xe, and (150)Nd based on state-of-the-art energy density functional methods using the Gogny D1S functional. Beyond-mean-field effects are included within the generating coordinate method with particle number and angular momentum projection for both initial and final ground states. We obtain a rather constant value for the NMEs around 4.7 with the exception of (48)Ca and (150)Nd, where smaller values are found. We analyze the role of deformation and pairing in the evaluation of the NME and present detailed results for the decay of (150)Nd.