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arXiv · hep-ex/0612050

Measurements of CP-Violating Asymmetries in B0 to a1(1260)^{+-} pi^{-+} Decays

The BABAR Collaboration·B. Aubert
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Abstract

We present measurements of CP-violating asymmetries in the decay B0 -> a_1(1260)^{+-} pi^{-+} with a_1(1260)^{+-} -> pi^{-+} pi^{+-} pi^{+-}. The data sample corresponds to 384 million B B-bar pairs collected with the BaBar detector at the PEP-II asymmetric B-factory at SLAC. We measure the CP-violating asymmetry A^{a_1 π}_{CP}=-0.07+-0.07+-0.02, the mixing-induced CP violation parameter S_{a_1 π}= 0.37 +-0.21+-0.07, the direct CP violation parameter C_{a_1 π}=-0.10+-0.15+-0.09, and the parameters ΔC_{a_1 π}=0.26+-0.15+-0.07 and ΔS_{a_1π}=-0.14+-0.21+-0.06. From these measured quantities we determine the angle α_{\rm eff}= 78.6^{\circ} +- 7.3^{\circ}.

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The BABAR Collaboration, B. Aubert. 2007-01-16. Measurements of CP-Violating Asymmetries in B0 to a1(1260)^{+-} pi^{-+} Decays. https://doi.org/10.1103/physrevlett.98.181803

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