Direct CP Asymmetry of B -> X_d γin the effective SUSY model

Akeroyd, A. G.; Keum, Y. -Y.; Recksiegel, S.

Direct CP Asymmetry of B -> X_d γin the effective SUSY model

Authors

Akeroyd, A. G.

Keum, Y. -Y.

Recksiegel, S.

Description

We investigate the effect of supersymmetric CP violating phases on the inclusive decay B\to X_dγ. Although such a decay contains a large background from B\to X_sγ, if isolated it may exhibit sizeable CP violation, both in the Standard Model (SM) and in the context of models beyond the SM. With unconstrained supersymmetric CP violating phases we show that the direct CP asymmetry (A_CP) lies in the region -40% \le A_CP \le 40%, where a positive asymmetry would constitute a clear signal of physics beyond the SM. Even if a direct measurement of B\to X_dγproves too dif ficult experimentally, its asymmetry contributes non-negligibly to the measurements of A_CP for B\to X_sγ, and thus should be included in future analyses. We show t hat there may be both constructive and destructive interference between A^dγ_CP and A^sγ_CP.
To appear in the proceedings of BCP4, Ise 2001. The original conference poster is available at http://www-th.kek.jp/home/stefan/b2dgamma/