Dipole coefficients in B -> X_s gamma in supersymmetry with large \tan\beta and explicit CP violation

Abstract

We perform a detailed study of the electric and chromoelectric dipole coefficients in B -> X_s \gamma decay in a supersymmetric scheme with explicit CP violation. In our analysis, we adopt the minimal flavor violation scheme by taking into account the \tan\beta-enhanced large contributions beyond the leading order. We show that the coefficients can deviate from the SM prediction significantly in both real and imaginary directions. Experimental bounds still allow for large deviations from the SM predictions for both dipole coefficients such that the CP asymmetry is as large as \pm 8%. There are further implications of these coefficients for the charmless hadronic and semileptonic B decays. As a direct application of our analysis, we have discussed \Lambda_b -> \Lambda \gamma decay.