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arXiv · hep-ex/0508007

Measurement of Branching Fraction and Direct CP Asymmetry in B0-->rho0 pi0 Decays

The Belle Collaboration
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Abstract

We report a measurement of the decay B0 --> rho0 pi0, using 386 x 10^6 BB-bar pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. We detect 51^{+14}_{-13} signal events with a significance of 4.2 standard deviations, including systematic uncertainties, and measure the branching fraction to be B(B0 --> rho0 pi0) = (3.12^{+0.88}_{-0.82} (stat) +/- 0.33 (syst) ^{+0.50}_{-0.68} (model)) x 10^{-6}. We also perform the first measurement of direct CP violating asymmetry in this mode.

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The Belle Collaboration. 2006-06-15. Measurement of Branching Fraction and Direct CP Asymmetry in B0-->rho0 pi0 Decays. https://doi.org/10.1103/physrevd.73.111105

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