Analysis of B→K∗ℓ+ℓ− decays at large recoil region Original Research Article

We study the exclusive decays of B→K∗ℓ+ℓ− within the framework of the perturbative QCD (PQCD). We obtain the form factors for the B→K∗ transition in the large recoil region, where the PQCD for heavy B meson decays is reliable. We find that our results for the form factors at q2=0 are consistent with those from most of the other QCD models in the literature. Via the decay chain of B→K∗(Kπ)ℓ+ℓ−, we obtain many physical observables related to the different helicity combinations of B→K∗ℓ+ℓ−. In particular, we point out that the T-violating effect suppressed in the standard model can be up to O(10%) in some CP violating models with new physics.