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Improved Measurements of CP-Violating Asymmetry Amplitudes in B0 -> pi+pi- Decays

B. Aubert·BaBar Collaboration
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Abstract

We present updated measurements of the CP-violating parameters S_pipi and C_pipi in B0 -> pi+pi- decays. Using a sample of 227 million Y(4S) -> BBbar decays collected with the BaBar detector at the PEP-II asymmetric-energy e+e- collider at SLAC, we observe 467 +- 33 signal decays and measure S_pipi = -0.30 +- 0.17 (stat) +- 0.03 (syst), and C_pipi = -0.09 +- 0.15 (stat) +- 0.04 (syst).

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B. Aubert, BaBar Collaboration. 2005-01-28. Improved Measurements of CP-Violating Asymmetry Amplitudes in B0 -> pi+pi- Decays. https://doi.org/10.1103/physrevlett.95.151803

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