Neutrinoless double-βdecay in left-right-symmetric models

We calculate neutrinoless double-$\beta$ decay due to doubly charged Higgs bosons, which occur naturally in left-right-symmetric models. We find that the comparison with known half-lives yields values of phenomenological parameters which are compatible with earlier analyses of neutral-current data. In particular, we obtain a right-handed gauge-boson mass lower bound of the order of 240 GeV. Using this result and expressions for neutrino masses derived in a parity-nonconserving left-right-symmetric model, we obtain $m_{{\nu }_e}\le 1.5$ eV, $m_{{\nu }_{\mu }}\le 0.05$ MeV, and $m_{{\nu }_{\tau }}\le 18$ MeV.