Probing new physics in B→K^(*)l⁺l^- decays

We study the exclusive decays of B→K^(*)l⁺l^- by results in perturbative QCD with the heavy quark effective theory and lattice calculations. We obtain the form factors for the B→K^(*) transitions in the whole allowed region. Our predictions for the branching ratios of B→Kl⁺l^-, B→K^*e⁺e^-, and B→K^*μ⁺μ^- are 0.53±0.05_-0.07^+0.10, 1.68±0.17_-0.09^+0.14, and 1.34±0.13_-0.06^+0.11×10^-6, where the errors are from the quark mixing elements and hadronic effects, respectively. We also find that our definitions of the T-odd observable and the up-down asymmetry of the K meson in B→K^*l⁺l^-→Kπl⁺l^- can be used to probe new physics.