Deformed shell model results for two-neutrino double-beta decay of 82Se

The half-life for two-neutrino double-beta decay has been calculated for Se-82, within the framework of the deformed shell model (DSM) based on Hartree-Fock states employing a modified Kuo interaction in (2)p(3/2), (1)f(5/2), P-2(1/2), and (1)g(9/2) space with single particle energies (relative to a Ni-56 core) for the four orbitals taken as 0.0, 0.78, 1.08, and 4.25 MeV, respectively. A reasonable description is obtained for the spectroscopic properties of yrast levels in Se-82, and similarly in the past Kr-82 was studied successfully using DSM. The half-life calculated using DSM is similar to 3.56 x 10(20) a compared to the experimental value (0.92 +/- 0.07) x 10(20) a. We have also recalculated the half-life by including the (1)f(7/2) orbit in the preceding model space using the fpg interaction introduced by Sorlin et al. (Phys. Rev. Lett. 88, 092501 (2002)). The calculated half-life is 2.05 x 10(19) a (0.58 x 10(2) a if we include the quenching factor of 0.77).