0 nu beta beta-decay nuclear matrix element for light and heavy neutrino mass mechanisms from deformed quasiparticle random-phase approximation calculations for Ge-76, Se-82, Te-130, Xe-136, and Nd-150 with isospin restoration

AbstraktAbstract

In this paper, with restored isospin symmetry, we evaluated the neutrinoless double-beta-decay nuclear matrix elements for Ge-76, Se-82, Te-130, Xe-136, and Nd-150 for both the light and heavy neutrino mass mechanisms using the deformed quasiparticle random-phase approximation approach with realistic forces. We give detailed decompositions of the nuclear matrix elements over different intermediate states and nucleon pairs, and discuss howthese decompositions are affected by the model space truncations. Compared to the spherical calculations, our results show reductions from 30% to about 60% of the nuclear matrix elements for the calculated isotopes mainly due to the presence of the BCS overlap factor between the initial and final ground states. The comparison between different nucleon-nucleon (NN) forces with corresponding short-range correlations shows that the choice of the NN force gives roughly 20% deviations for the light exchange neutrino mechanism and much larger deviations for the heavy neutrino exchange mechanism.

In this paper, with restored isospin symmetry, we evaluated the neutrinoless double-beta-decay nuclear matrix elements for Ge-76, Se-82, Te-130, Xe-136, and Nd-150 for both the light and heavy neutrino mass mechanisms using the deformed quasiparticle random-phase approximation approach with realistic forces. We give detailed decompositions of the nuclear matrix elements over different intermediate states and nucleon pairs, and discuss howthese decompositions are affected by the model space truncations. Compared to the spherical calculations, our results show reductions from 30% to about 60% of the nuclear matrix elements for the calculated isotopes mainly due to the presence of the BCS overlap factor between the initial and final ground states. The comparison between different nucleon-nucleon (NN) forces with corresponding short-range correlations shows that the choice of the NN force gives roughly 20% deviations for the light exchange neutrino mechanism and much larger deviations for the heavy neutrino exchange mechanism.