Study of B0 → π0π0, B± → π±π0, and B± → K±π0 decays, and isospin analysis of B → ππ decays

Abstract

We present updated measurements of the branching fractions and C P asymmetries for B 0 → π 0 π 0 , B ± → π ± π 0 , and B ± → K ± π 0 . Based on a sample of 383 × 10 6 Υ ( 4 S ) → B ¯¯¯ B decays collected by the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC, we measure B ( B 0 → π 0 π 0 ) = ( 1.47 ± 0.25 ± 0.12 ) × 10 − 6 , B ( B ± → π ± π 0 ) = ( 5.02 ± 0.46 ± 0.29 ) × 10 − 6 , and B ( B ± → K ± π 0 ) = ( 13.6 ± 0.6 ± 0.7 ) × 10 − 6 . We also measure the C P asymmetries C π 0 π 0 = − 0.49 ± 0.35 ± 0.05 , A π ± π 0 = 0.03 ± 0.08 ± 0.01 , and A K ± π 0 = 0.030 ± 0.039 ± 0.010 . Finally, we present bounds on the Cabibbo-Kobayashi-Maskawa angle α using isospin relations.