Constraints on SUSY Gluonic Dipole Interaction from B\to K\pi Decays

Abstract

In low energy SUSY theories exchange of gluino and squark with left-right mixing can produce a large gluonic dipole interaction. In this paper we study the effects of this interaction on $B\to K \pi$ using QCD improved factorization method. The Standard Model predicts a smaller branching ratio for $B^0 \to \bar K^0 \pi^0$ than experimental measured one. We find that within the parameter space allowed from $B\to \gamma X_s$ constraint, the SUSY dipole interaction can enhance this branching ratio to agree with the experimental measurement. Combining recent data for all the four $\bar B^0 \to K^- \pi^+, \bar K^0 \pi^0$ and $B^- \to K^- \pi^0, \bar K^0 \pi^-$ decay modes, we find that the allowed parameter space is reduced significantly compared with that using $B\to X_s \gamma$ data alone. It is found that even with these constraints, the predictions for CP violation in these modes can be dramatically different from those of the SM predictions.