The measurement of the partial rate asymmetries for various B -> K pi decay modes is presented. A significant asymmetry is measured for the decay mode B -> K+pi(-) with A(CP) = -0.101 +/- 0.025 +/- 0.005 which has a significance of 3.9 sigma and thus indicates evidence for direct CP violation. Furthermore the first observation of the decay mode B -> pi(0)pi(0) with a branching fraction of B(B -> pi(0)pi(0)) = 2.3(-0.5)(+0.4) +/- 0.2 x 10(-6) having a significance of 6.0 sigma is presented accompanied with the first measurement of the CP asymmetry in this mode.
机构:
Penn State Coll Med, Dept Obstet & Gynecol, 500 Univ Dr, Hershey, PA 17033 USAPenn State Coll Med, Dept Obstet & Gynecol, 500 Univ Dr, Hershey, PA 17033 USA