THE EFFECT OF Z′-MEDIATED FLAVOR-CHANGING NEUTRAL CURRENT ON Bd→ℓ+ℓ- DECAY

Abstract

We study the effect of both Z and Z′-mediated flavor-changing neutral current (FCNC) on the Bd→ℓ+ℓ-, (ℓ = μ, τ) rare decay. We find that the branching ratio can be larger by order two from its Standard Model (SM) value due to the effect of both Z and Z′-mediated FCNC, though the major contribution comes from Z boson and provides signals for new physics beyond the SM.