Renormalization Group Induced Neutrino Masses in Supersymmetry without R-parity

We study supersymmetric models without R parity and with universal soft supersymmetry breaking terms. We show that as a result of the renormalization group flow of the parameters, a misalignment between the directions in field space of the down-type Higgs vacuum expectation value vd and of the μ term is always generated. This misalignment induces a mixing between the neutrinos and the neutralinos, resulting in one massive neutrino. By means of a simple approximate analytical expression, we study the dependence on the different parameters that contribute to the misalignment and to mν . In large part of the parameter space this effect dominates over the standard one-loop contributions to mν ; we estimate 1 MeV < ∼ mν < ∼ 1 GeV. Laboratory, cosmological and astrophysical constraints imply mν < ∼ 100 eV. To be phenomenologically viable, these models must be supplemented with some additional mechanism to ensure approximate alignment and to suppress mν . E-mail address: [email protected]