Lepton Flavor Violation in SUSY models with U(1)-textures

Abstract

U(1)-family symmetries have led to successful predictions of the fermion mass spectrum and the mixing angles of the hadronic sector. In the context of the supersymmetric unified theories, they further imply a non-trivial mass structure for the scalar partners, giving rise to new sources of flavour violation. While tau->mu gamma decays are mostly expected to arise at rates significantly smaller than the current experimental limits, the mu -> e gamma rare decays impose important bounds on the model parameters. Even if universal soft-terms are assumed at the GUT scale, when massive neutrinos are included in these theories, new mixings appear in the soft-terms. The predicted branching ratios for rare decays are in this case below the experimental bounds.