An alternative approach to $b \to s\gamma$ in the unconstrained MSSM

The gluino contributions to the $C'_{7,8}$ Wilson coefficients for b->s\gamma are calculated within the unconstrained MSSM. New stringent bounds on the \dRLbs and \dRRbs mass insertion parameters are obtained in the limit in which the SM and SUSY contributions to $C_{7,8}$ approximately cancel. Such a cancellation can plausibly appear within several classes of SUSY breaking models. Assuming this cancellation takes place, we perform an analysis of the b->s\gamma decay. We show that, in the unconstrained MSSM such an alternative is reasonable and it is possible to saturate the b->s\gamma branching ratio and produce a CP asymmetry of up to 20%, from only the gluino contribution to $C'_{7,8}$ coefficients. Using photon polarization a LR asymmetry can be defined that in principle allows the $C_{7,8}$ and $C'_{7,8}$ contributions to the b->s\gamma decay to be disentangled.