A measurement of sin 2 β from B → J / ψK 0 S with the CDF detector
نویسندگان
چکیده
This paper reports an updated measurement of the Standard Model CP violation parameter sin 2β using the CDF Detector at Fermilab. The entire Run I data sample of 110 pb−1 of proton antiproton collisions at √ s = 1.8TeV is used to identify a signal sample of ∼400 B → J/ψK0 S events, where J/ψ → μ+μ− and K0 S → π+π−. The flavor of the neutral B meson is identified at the time of production by combining information from three tagging algorithms: a same-side tag, a jet-charge tag, and a soft-lepton tag. A maximum likelihood fitting method is used to determine sin 2β = 0.79 −0.44 (stat+syst). This value of sin 2β is consistent with the Standard Model prediction, based upon existing measurements, of a large positive CP violating asymmetry in this decay mode. PACS numbers: 12.15.Hh, 13.20.He, 14.40.Nd Typeset using REVTEX
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تاریخ انتشار 1999