Phenomenology of R-parity violation and neutrino mass

Abstract

We study various phenomenological implications of R-parity violating interactions and neutrino masses in supersymmetric models. Supersymmetry has been introduced to solve the gauge hierarchy problem. Minimal Supersymmetric Standard Model requires extra discrete symmetry which would forbid the rapid proton decay. Models which conserve baryon number and allow for small lepton number violation explain non-zero neutrino masses while avoiding rapid proton decay. We first review the basic materials of supersymmetry and present the important consequences of R-parity violation. R-parity violating interactions can contribute to various low energy processes via the exchange of virtual superparticles. The upper limits on trilinear R-parity violating couplings can be deduced from such processes under the assumption of single coupling dominance. All these bounds are collected and systematically reviewed. We also dicuss the new contributions, which contains both bilinear and trilinear R-parity violating interactions, to the fermion EDM and several lepton number violating processes like μ→eγ↔, μ→eee, μ↔e conversion. One loop contributions to the neutrino mass matrix in R-parity violating supersymmetric models are studied and expressed in terms of basis independent quantities. We investigate the possibility of explaining all the fermion mass hierarchy in terms of flavor U(1) symmetry, including the neutrino mass and mixing structure suggested by neutrino oscillation experiments. A general formulation of sneutrino - antisneutrino mixing phenomena is presented in the field theory approach and applied to the anomaly mediated supersymmetry breaking models and R-parity violating models.