Signals of extra gauge bosons and exotic leptons in SU(6)$_{L}\otimes$U(1)$_{Y}$

Abstract

We study some of the consequences of the SU(6)$_{L}\otimes$U(1)$_{Y}$ model of unification of electroweak interactions and families with a horizontal gauge group SU(2)$_{H}$, paying special attention to processes with flavor changing neutral currents. We compute at tree level the decays $K^{+}\longrightarrow π^{+}μ^{+}e^{-}$, $K_L^0\longrightarrow μ^{+}e^{-}$ and $μ^{-} \longrightarrow e^{-} \bar{ν_e} ν_μ$ from which we obtain lower bounds for the mass of the horizontal gauge boson associated with FCNC. Finally we obtain limits on the mixing between ordinary and exotic charged leptons.