Measurements of Lifetimes, Mixing and CP Violation of B Mesons with the BABAR Detector
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چکیده
Using a data sample of 62 million Υ (4S) → BB decays collected between 1999 and 2001 by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC we study events in which one neutral B meson is fully reconstructed in a final state containing a charmonium meson and the flavour 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 sin2β, is derived from the decay time distributions. We measure sin2β = 0.75 ± 0.09 (stat) ± 0.04 (syst) and |λ| = 0.92 ± 0.06 (stat) ± 0.02 (syst). The latter is consistent with the Standard Model expectation of no direct CP violation. These results are preliminary. In addition, we report on precision measurements of the B lifetimes, and the B 0-B 0 oscillation frequency ∆m d .
منابع مشابه
CP Violation in B decays to Charmonium and Charm Final States at BABAR
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