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

The BABAR Collaboration·B. Aubert
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Abstract

We present a measurement of time-dependent CP asymmetries and an updated determination of the CP-odd fraction in the decay B0 --> D*+D*- using a data sample of 88 x 10^6 BBbar pairs collected by the BABAR detector at the PEP-II B Factory at SLAC. We determine the CP-odd fraction to be 0.063 +/- 0.055(stat) +/- 0.009(syst). The time-dependent CP asymmetry parameters $Im(λ_+)$ and $|λ_+|$ are determined to be 0.05 +/- 0.29(stat) +/- 0.10(syst) and 0.75 +/- 0.19(stat) +/- 0.02(syst), respectively. The Standard Model predicts these parameters to be -sin2beta and 1, respectively, in the absence of penguin diagram contributions.

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The BABAR Collaboration, B. Aubert. 2003-06-25. Measurement of Time-Dependent CP Asymmetries and the CP-Odd Fraction in the Decay B0 --> D*+D*-. https://doi.org/10.1103/physrevlett.91.131801

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