Neutrinoless double beta decay, neutrino mass and bilinear R-parity breaking supersymmetry

Neutrinoless double beta (ββ0ν) decay violates lepton number; its absence stringently constrains the parameters of theories beyond the standard model in which the neutrino has a Majorana mass. R-parity violating weak-scale supersymmetry is a prominent example of such models. Double beta decay in supersymmetry with explicit bilinear R-parity breaking is discussed and current limits on the ββ0ν decay half life of Ge are used to extract upper bounds on the R-parity breaking parameters of the first generation. Moreover, it is shown that the effective Majorana neutrino mass, measured in ββ0ν decay, is non-zero once the 1-loop corrections are taken into account even for the case of perfect alignment (Λi := (〈ν̃i〉μ− v1ǫi) ≡ 0) among the R-parity violating parameters.