NEUTRINO MASSES AND MIXING ANGLES IN SUSY-GUT THEORIES WITH EXPLICIT R-PARITY BREAKING

In minimal SUSY GUT models the R-parity breaking terms are severely co nstrained by SU(5) gauge invariance. We consider the particular case w here the explicit R-parity breaking occurs only via dimension-2 terms of the superpotential. This model possesses only three R-parity breaki ng parameters. We have studied the predictions of this model for the n eutrino masses and mixing angles at the one-loop level within the fram ework of a radiatively broken unified supergravity model. We find that this model naturally yields masses and mixing angles that can explain the solar and atmospheric neutrino problems. In addition, there are r egions in parameter space where the solution to the solar neutrino puz zle is compatible with either the LSND result or the existence of sign ificant hot dark matter neutrinos.