Deformed HF calculation for ⁷⁶Ge ⁷⁶Se double-beta decay

The two-neutrino double-beta decay (2-decay) for ⁷⁶Ge ⁷⁶Se is studied within the framework of the deformed Hartree-Fock formalism. An interaction given by Kuo and modified by Ahalpara et al is used. The results of our model calculation are compared with those obtained using the shell model and the quasiparticle random phase approximation. The role of the deformation, pairing and Coulomb interaction in double-beta decay is investigated. We have found that the inclusion of both deformation and pairing influences the 2-decay matrix element significantly.