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arXiv · hep-ex/0102030

Measurement of CP-violating asymmetries in B0 decays to CP eigenstates

The BABAR Collaboration·B. Aubert
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Abstract

We present measurements of time-dependent CP-violating asymmetries in neutral B decays to several CP eigenstates. The measurement uses a data sample of 23 million Upsilon(4S)-->B-anti-B decays collected by the BABAR detector at the PEP-II asymmetric B Factory at SLAC. In this sample, we find events where one neutral B meson is fully reconstructed in a CP eigenstate containing charmonium and the flavor of the other neutral B meson is determined from its decay products. The amplitude of the CP-violating asymmetry, which in the Standard Model is proportional to sin2beta, is derived from the decay time distributions in such events. The result is sin2beta=0.34 +/- 0.20 (stat) +/- 0.05 (syst).

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The BABAR Collaboration, B. Aubert. 2001-02-23. Measurement of CP-violating asymmetries in B0 decays to CP eigenstates. https://doi.org/10.1103/physrevlett.86.2515

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