R-parity violation: origin of μ-term and other consequences

Abstract

We propose a new mechanism in which the generation of the supersymmetric μ -term as well charged lepton masses is closely tied to R -parity violation involving heavy vector-like families. A realistic example based on SU (3) c × SU (2) L × U (1) Y , supplemented by the symmetry R × U (1) , is presented, where R ( U (1) ) denotes a continuous R (flavor) symmetry. In addition to the μ -term, the charged fermion mass hierarchies and mixings, as well as baryon number conservation are also nicely explained. Bilinear R -parity violating coupling involving the first generation gives rise to neutrino mass relevant for the small angle ν e − ν s MSW oscillations, where ν s denotes a sterile state. The atmospheric neutrino puzzle is resolved via maximal mixing angle ν μ − ν τ oscillations. The decay of the lightest neutralino (LSP) and leptogenesis are briefly discussed.