QCD Sum Rule Analysis of B \to (K,K^*) (\ell^+\ell^-,\nu\bar\nu) Decays

Abstract

We use three-point QCD sum rules to calculate the form factors governing the rare exclusive decays B \to (K,K^*) \ell^+ \ell^-, B \to (K,K^*) \nu \bar\nu. We predict the branching ratios, the invariant mass distributions of the lepton pair for B \to (K,K^*) \ell^+ \ell^-, and the spectra of missing energy for B \to (K,K^*) \nu \bar\nu. The forward-backward asymmetry in B \to K^* \ell^+ \ell^- provides us with interesting tests of the Standard Model and its extensions.