2-NEUTRINO DOUBLE-BETA DECAY HALF-LIVES OF ZR-96 AND MO-100 TO EXCITED-STATES OF MO-96 AND RU-1OO

Two-neutrino double-beta decay half-lives for the transitions to the f irst excited 2(+) and 0(+) states have been computed in the framework of a second quasi random phase aproximation (QRPA) in the cases of Mo- 100 and Zr-96. In addition, other single-beta decay rates and B(E2) tr ansitions related to the same nuclei are evaluated and compared with e xperimental data. We have found a good agreement between theory and ex periment for all the computed quantities except the B(E2) transitions in Mo-100 and Ru-100. For the beta beta decay transitions studied we p redict half-lives of the order of 10(21)-10(22) y.