Precise Measurement of the CP Violation Parameter sin2 phi(1) in B-0 -> (c(c)over-bar) K-0 Decays

Abstract

We present a precise measurement of the CP violation parameter sin2 phi(1) and the direct CP violation parameter A(f) using the final data sample of 772 x 10(6) B (B) over bar pairs collected at the Y(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. One neutral B meson is reconstructed in a J / psi K-S(0), psi (2S)K-S(0), chi K-c1(S)0, or J / psi K-L(0) CP eigenstate and its flavor is identified from the decay products of the accompanying B meson. From the distribution of proper-time intervals between the two B decays, we obtain the following CP violation parameters: sin2 phi(1) = 0.667 +/- 0.023(stat) +/- 0.012(syst) and A(f) = 0.006 +/- 0.016(stat) +/- 0.012(syst).