We present a precise measurement of the CP violation parameter sin2 1 and the direct CP violation parameter Af using the final data sample of 772×106 BB̄ pairs collected at the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e +e- collider. One neutral B meson is reconstructed in a J/ψKS0, ψ(2S)KS0, χc1KS0, or J/ψKL0 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: sin21=0.667±0. 023(stat)±0.012(syst) and Af=0.006±0.016(stat) ±0.012(syst).
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)