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An alternative approach to b->sγin the unconstrained MSSM

Stefano Rigolin
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Abstract

The gluino contributions to the $C'_{7,8}$ Wilson coefficients for b->sγare 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->sγdecay. We show that, in the unconstrained MSSM such an alternative is reasonable and it is possible to saturate the b->sγbranching 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->sγdecay to be disentangled.

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Stefano Rigolin. 2002-04-15. An alternative approach to b->sγin the unconstrained MSSM. https://arxiv.org/abs/hep-ph/0204169

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