Ushiroda, Y (reprint author), High Energy Accelerator Res Org, Tsukuba, Ibaraki, Japan.
We present a new measurement of CP-violation parameters in B-0-> K(S)(0)pi(0)gamma decay based on a sample of 275x10(6) B (B) over bar pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB energy-asymmetric e(+)e(-) collider. One of the B mesons is fully reconstructed in the B-0-> K(S)(0)pi(0)gamma decay. The flavor of the accompanying B meson is identified from its decay products. CP-violation parameters are obtained from the asymmetry in the distribution of the proper time intervals between the two B decays. We obtain S(KS)(0)pi(0)gamma=-0.58(-0.38)(+0.46)(stat)+/- 0.11(syst) and A(KS)(0)pi(0)gamma=+0.03 +/- 0.34(stat)+/- 0.11(syst), for the K(S)(0)pi(0) invariant mass covering the full range up to 1.8 GeV/c(2). We also measure the CP-violation parameters for the case B-0-> K-*0(-> K(S)(0)pi(0))gamma and obtain S(K)(*0)gamma=-0.79(-0.50)(+0.63)(stat)+/- 0.10(syst) for A(K)(*0)gamma fixed at 0.