Predictions for $B\to \tau \bar{\mu }+\mu \bar{\tau }$

The observation of $B\to \tau \bar{\mu }+\mu \bar{\tau }$ at present experiments would be a clear sign of new physics. In this paper we calculate this process in a 2HDM framework where the decay is mediated by the exchange of spin zero particle with flavour changing neutral current couplings. If we identify the scalar with the the newly discovered state at LHC with a mass $% \sim 125 $GeVthenweget$BR(B_s \to \tau \bar{\mu} + \mu \bar{\tau}) \sim 10^{-6}$and$BR(B_d \to \tau \bar{\mu} + \mu \bar{\tau}) \sim 10^{-7}$. We also calculate this process in minimal supersymmetric standard model and find $BR(B_s\to \tau \bar{\mu }+\mu \bar{\tau })\sim {10}^{-11}$.