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Measurement of CP-Violating Asymmetries in $B^0\to(ρπ)^0$ Using a Time-Dependent Dalitz Plot Analysis

The BABAR Collaboration·B. Aubert
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Abstract

We report a measurement of CP-violating asymmetries in $B^0\to(ρπ)^0\toπ^+π^-π^0$ decays using a time-dependent Dalitz plot analysis. The results are obtained from a data sample of 347 million $Υ(4S) \to B\bar{B}$ decays, collected by the BaBar detector at the PEP-II asymmetric-energy B Factory at SLAC. We measure 26 coefficients of the bilinear form factor terms occurring in the time-dependent decay rate of the \Bz meson and derive the physically relevant quantities from these coefficients. In particular we find a three standard deviation evidence of direct CP-violation in $B^0\toρ^\pmπ^\mp$ decays, with systematic uncertainties included. We also achieve a constraint of the angle $α$ of the Unitarity Triangle. All results presented are preliminary.

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The BABAR Collaboration, B. Aubert. 2006-09-20. Measurement of CP-Violating Asymmetries in $B^0\to(ρπ)^0$ Using a Time-Dependent Dalitz Plot Analysis. https://arxiv.org/abs/hep-ex/0608002

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