RENORMALIZED PROTON-NEUTRON QRPA AND DOUBLE-BETA DECAY OF SE-82 TO EXCITED-STATES IN KR-82

We apply the self-consistent renormalized proton-neutron QRPA (RQRPA) method to calculate the two-neutrino double beta (2 nu beta beta) deca y matrix elements associated with the ground-state and excited-state t ransitions of the Se-82 --> Kr-82 decay. The RQRPA method is an extens ion of the pnQRPA method and promotes the Pauli exclusion principle vi olated by the pnQRPA ground state and yields more stable nuclear matri x elements with increasing strength of the proton-neutron interaction. In the present work the RQRPA wave functions are also used to evaluat e 2 nu beta beta-decay rates to excited final states. The resulting th eoretical half lives are compared with the new stringent experimental limits obtained by using a HPGe detector and external sources of enric hed selenium.