Testing the Standard Model in $B\to K^{(*)} \ell^+\ell^-$

Abstract

We study the potential of $B\to K^{(*)} \ell^+\ell^-$ decays as tests of the standard model. After discussing the reliability of theoretical predictions for the hadronic matrix elements involved, we examine the impact of different new physics scenarios on various observables. We show that the angular information in \bks together with the dilepton mass distribution can highly constrain new physics. This is particularly true in the large dilepton mass region, where reliable predictions for the hadronic matrix elements can be made with presently available data. We compare the Standard Model predictions with those of a Two-Higgs doublet model as well as TopColor models, all of which give distinct signals in this region.