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Measurement of the Time-Dependent CP Asymmetry in the B0 --> Phi K0 Decay

B. Aubert·BABAR Collaboration
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Abstract

We present a measurement of the time-dependent CP asymmetry for the neutral B-meson decay B0 --> Phi K0. We use a sample of approximately 114 million B-meson pairs taken at the Upsilon(4S) resonance with the BaBar detector at the PEP-II B-meson Factory at SLAC. We reconstruct the CP eigenstates Phi K0_S and Phi K0_L where Phi --> K+ K-, K0_S --> pi+ pi-, and K0_L is observed via its hadronic interactions. The other B meson in the event is tagged as either a B0 or B0-bar from its decay products. The values of the CP-violation parameters are S = 0.47 +/- 0.34 (stat) +0.08/-0.06 (syst) and C = 0.01 +/- 0.33 (stat) +/- 0.10 (syst).

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B. Aubert, BABAR Collaboration. 2004-03-16. Measurement of the Time-Dependent CP Asymmetry in the B0 --> Phi K0 Decay. https://doi.org/10.1103/physrevlett.93.071801

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