Quasi-random phase approximation analysis of two-neutrino double-beta decay to the first 2~+ state of ~(128,130)Xe isotopes

摘要

Quasi-random phase approximation analysis of the two-neutrino double-beta decay to the first 2~+ state of ~(128,130)Xe isotopes is presented in this work. The wave functions of the first 2~+ state have been obtained within the charge-conserving quasiparticle randsom phase approximation (QRPA) ((pp + nn)QRPA) with the effective interactions in the particle-hole and particle-particle channels. The intermediate states have been calculated within the charge-exchange QRPA proton-neutron QRPA (pnQRPA). The stability of the nuclear matrix element for the two-neutrino double-beta decay to the first 2~+ state has been studied by calculating its dependence on the strength parameter of the particle-particle interaction in the pnQRPA calculations and the double-beta decay half-lives have been calculated. The obtained results have been compared with the corresponding experimental data.