Study of Exclusive Radiative B Meson Decays

Abstract

We have investigated exclusive, radiative B meson decays to charmless mesons (ρ, ω, ϕ, K^*(892), K^*_2(1430)) in 9.7\times 10^6 BBbar decays accumulated with the CLEO detector. The B -> K^*(892)γbranching fractions are determined to be Br(B^0 -> K^{*0}(892)γ) = (4.55 +0.72-0.68 +-0.34)\times 10^-5 and Br(B^+ -> K^{*+}(892)γ) = (3.76 +0.89-0.83 +-0.28)\times 10^-5. We have searched for CP asymmetry in B -> K^*(892)γdecays and measure Acp = +0.08 +-0.13 +-0.03. We also report the first observation of the decay B -> K^*_2(1430)γwith a branching fraction of (1.66 +0.59-0.53 +-0.13)\times 10^-5 and determine $Br(B -> K^*_2(1430)γ)/Br(B -> K^*(892)γ) = 0.39 +0.15-0.13 consistent with only one of two available theoretical models. No significant evidence for the decays B -> ργand B^0 -> ωγis found and we limit Br(B -> (ρ/ω)γ)/Br(B -> K^{*}(892)γ) < 0.32 at 90% CL. We also find no evidence for the exotic decay B^0 -> ϕγ.