Effect of FCNC mediated Z boson on lepton flavor violating decays (1011.4184v2)
Abstract: We study the three body lepton flavor violating (LFV) decays $\mu- \to e- e+ e-$, $\tau- \to l_i- l_j+ l_j-$ and the semileptonic decay $\tau \to \mu \phi $ in the flavor changing neutral current (FCNC) mediated $Z$ boson model. We also calculate the branching ratios for LFV leptonic B decays, $B_{d,s} \to \mu e$, $B_{d,s} \to \tau e$, $B_{d,s} \to \tau \mu$ and the conversion of muon to electron in Ti nucleus. The new physics parameter space is constrained by using the experimental limits on $\mu- \to e- e+ e-$ and $\tau- \to \mu- \mu+ \mu-$. We find that the branching ratios for $\tau \to eee $ and $\tau \to \mu \phi$ processes could be as large as $\sim {\cal O}(10{-8})$ and ${\rm Br}B_{d,s} \to \tau \mu, \tau e) \sim {\cal O}(10{-10})$. For other LFV B decays the branching ratios are found to be too small to be observed in the near future.