Evidence for CP Violation in B⁺ → K*(892)⁺π⁰ from a Dalitz Plot Analysis of B⁺ → K_s⁰π⁺π⁰ Decays



We report a Dalitz plot analysis of charmless hadronic decays of charged B mesons to the final state K_s⁰ π⁺π⁰ using the full BABAR data set of 470.9 ± 2.8 million BB̅ events collected at the Υ(4S) resonance. We measure the overall branching fraction and CP asymmetry to be Β(B⁺ → K⁰ π⁺π⁰) = (31.8 ± 1.8 ± 2.1_{-0.0}^{+6.0}) x 10⁻⁶ and A_{CP}(B⁺ → K⁰ π⁺π⁰) = 0.07 ± 0.05 ± 0.03_{-0.03}^{+0.02}, where the uncertainties are statistical, systematic, and due to the signal model, respectively. This is the first measurement of the branching fraction for B⁺ → K⁰ π⁺π⁰. We find first evidence of a CP asymmetry in B⁺ → K*(892)⁺π⁰ decays: A_{CP}(B⁺ → K*(892)⁺π⁰) = -0.52 ± 0.14 ± 0.04_{-0.02}^{+0.04}. The significance of this asymmetry, including systematic and model uncertainties, is 3.4 standard deviations. We also measure the branching fractions and CP asymmetries for three other intermediate decay modes.



Nuclear isobars, Mesons, Electron-positron interactions, Charge-parity asymmetry, Charge-parity violations, Branching fractions (Nuclear physics), Hadrons—Decay



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