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A Study of Time-Dependent CP Asymmetry in B0 --> J/psi pi0 Decays

The BABAR Collaboration·B. Aubert
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Abstract

We present our first study of the time-dependent CP-violating asymmetry in B0 --> J/psi pi0 decays using e^+e^- annihilation data collected with the BABAR detector at the Y(4S) resonance during the years 1999--2002 at the PEP-II asymmetric-energy B Factory at SLAC. With about 88 million B Bbar pairs, our preliminary results for the coefficients of the cosine and sine terms of the CP asymmetry are C_{J/psi pi0} = 0.38 +/- 0.41 (stat) +/- 0.09 (syst) and S_{J/psi pi0} = 0.05 +/- 0.49 (stat) +/- 0.16 (syst).

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The BABAR Collaboration, B. Aubert. 2003-05-19. A Study of Time-Dependent CP Asymmetry in B0 --> J/psi pi0 Decays. https://arxiv.org/abs/hep-ex/0207058

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