DIRECT CP ASYMMETRY IN B → X_dγ AND B → X_sγ IN THE EFFECTIVE SUSY–MODEL

We study the effect of large CP violating phases in the effective Supersymmetric theory on the direct CP asymmetry in the decays B → X_dγ and B → X_sγ. With unconstrained Supersymmetric CP violating phases we show that the direct CP asymmetry for b → dγ (b → sγ) lies in the region , where a positive (negative) asymmetry would constitute a clear signal of physics beyond the SM. Even if a direct measurement of B → X_dγ proves too difficult experimentally, its asymmetry contributes non–negligibly to the measurements of , for B → X_sγ and thus should be included in future analyses.