Lepton flavour violating Higgs boson decays, tau ->mu gamma and B-s ->mu (+) mu(-) in the constrained MSSM+nu(R) with large tan beta

Abstract

Realistic predictions are made for the rates of lepton flavour violating Higgs boson decays, tau -> mu gamma, mu -> e gamma, B-S(0) -> mu mu, B-s(0) -> tau mu and tau -> 3 mu via a top-down analysis of the minimal supersymmetric -V s Standard Model (MSSM) constrained by SU(5) unification with right-handed neutrinos and large tan beta The third family neutrino Yukawa coupling is chosen to be of order 1, in this way our model bares a significant resemblance to supersymmetric SO(10). In this framework the large PMNS mixings result in potentially large lepton flavour violation. Our analysis predicts tau -> mu gamma and mu -> e gamma rates in the region (10(-8)-10(-6)) and (10(-11)-10(-14)), respectively. We also show that the rates for lepton flavour violating Higgs decays can be as large as 10(-7). The non-decoupling nature of H-0 -> tau mu is observed which leads to its decay rate becoming comparable to that for tau - mu gamma for large values of m(0) and M-1/2. We also find that the present bound on B-s -> mu mu is an important constraint on the rate of lepton flavour violating Higgs decays. The recently measured B-s-B-s mixing parameter Delta M-s, is also investigated. (c) 2006 Elsevier B.V. All rights reserved.