Implications of the nonuniversal Z boson in flavor changing neutral current mediated rare decays

Abstract

We analyze the effect of the nonuniversal Z boson in the rare decays Bs→l+l-, Bs→l+l-γ, and Z→bs̄ decays. These decays involve the flavor changing neutral current (FCNC) mediated b→s transitions, and are found to be very small in the standard model. The smallness of these decays in the standard model makes them sensitive probe for new physics. We find an enhancement of at least an order in these branching ratios because of the nonuniversal Zbs coupling. © 2005 The American Physical Society.