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arXiv · 0708.1549

Improved Measurement of Time-Dependent CP Asymmetries and the CP-Odd Fraction in the Decay B0->D*+D*-

BaBar Collaboration·B. Aubert
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Abstract

We present an updated measurement of the CP-odd fraction and the time-dependent CP asymmetries in the decay B0->D*+D*-using (383 +/- 4) \times 10^{6} BB pairs collected with the Babar detector. We determine the CP-odd fraction to be $0.143\pm0.034\stat\pm0.008\syst$. The time-dependent CP asymmetry parameters are determined to be $C_+ = -0.05\pm 0.14\stat \pm 0.02\syst$ and $S_+ = -0.72 \pm 0.19\stat \pm 0.05\syst$. The non-zero value of the measured $S_+$ indicates the evidence of CP violation at the $3.7 σ$ confidence level.

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BaBar Collaboration, B. Aubert. 2008-01-02. Improved Measurement of Time-Dependent CP Asymmetries and the CP-Odd Fraction in the Decay B0->D*+D*-. https://doi.org/10.1103/physrevd.76.111102

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