Calculation of Rare Decay B^+ \to D_s^+ \bar K^{*0} in Perturbative QCD Approach

The rare decay B^+ \to D_s^+ \bar K^{*0} can occur only via annihilation diagrams in the Standard Model. We calculate the branching ratio in perturbative QCD approach based on k_T factorization theorem. We found that the branching ratio of this decay is about of order 10^{-8}, which may be sensitive to new physics.