Theoretical description of double β decay of 160Gd

The half-life of the ββ2ν decay of 160Gd is estimated by including the pairing interaction within the pseudo-SU(3) model. This process was previously reported as theoretically forbidden in the context of that model, however, the pairing interaction is able to mix different occupations and opens new channels for the decay. Explicit expressions are presented for the mixing induced by the pairing force. Matrix elements for the ββ2ν and ββ0ν decays are now calculated by assuming both a dominant component in the wave function of the ground state of 160Gd and a more general model space. The results, of the calculated ββ half-lives, suggest that the planned experiments would succeed in detecting the ββ2ν decay of 160Gd and, eventually, would improve the limits for the zero-neutrino mode