Time-Dependent CP Asymmetries in B0 -> Ks Pi0 gamma transition

Abstract

We present measurements of CP-violation parameters in b -> s gamma transitions based on a sample of 386x10^6 BB pairs collected at the Y(4S) resonance with the Belle detector at the KEKB energy-asymmetric e+e- collider. One neutral B meson is fully reconstructed in the B0 -> Ks Pi0 gamma decay channel irrespective to the Ks Pi0 intermediate state. The flavor of the accompanying B meson is identified from its decay products. CP-violation parameters are obtained from the asymmetries in the distributions of the proper-time intervals between the two B decays. We obtain the following results for the Ks Pi0 invariant mass covering the full range up to 1.8 GeV/c^2: S_{Ks Pi0 gamma} = +0.08 +-0.41(stat) +-0.10(syst), A_{Ks Pi0 gamma} = +0.12 +-0.27(stat) +-0.10(syst).