Searching for supersymmetry in rare B decays

We quantify the ability of B factories to observe supersymmetric contributions to the rare decays B-->X-s gamma and B -->X(s)l(+)l(-). A global fit to the Wilson coefficients which contribute to these decays is performed from Monte Carlo generated data on B(B --> X-s gamma and the kinematic distributions associated with the final state lepton pair in B --> X(s)l(+)l(-). This fit is then compared to supersymmetric predicitons. Evaluation of the Wilson coefficients is carried out with several different patterns of the superpartner spectrum. We find that B factories will be able to probe regions of the supersymmetry parameter space not accessible to CERN LEP Il, the Fermilab Tevatron, and perhaps the CERN LHC. We also employ the recent NLO calculation of the matrix elements for B --> X-S gamma and find the bound m(H)+/- > 300 GeV in two-Higgs-doublet models using present data.