Neutrino mixing and lepton flavour violation in SUSY-gut models

Abstract

Presented at the XXVII International Conference of Theoretical Physics, "Matter to the Deepest", Ustron, Poland, september 15-21, 2003. ; In supersymmetric (SUSY) models the misalignment between fermion and sfermion families introduces unsuppressed flavour-changing processes. Even if the mass parameters are chosen to give no flavour violation, family dependent radiative corrections make this adjustment not stable. In par- ticular, due to the observed large neutrino mixings and potentially large neutrino Yukawa couplings, sizable lepton flavour violation (LFV) is ex- pected. After introducing the basic concepts, the framework and the main assumptions, we report on a recent study of rare leptonic decays in a class of SUSY–GUT models with three quasi-degenerate neutrinos. We show that LFV effects are likely visible in forthcoming experiments. ; This work has been supported by the Spanish CICYT, the Junta de Andalucía and the European Union under contracts FPA2000-1558, FQM 101, and HPRN-CT-2000-00149, respectively.