Measurement Of Sin 2 Beta From B -> J/Psi K-S(0) With The Cdf Detector

This paper reports an updated measurement of the standard model CP violation parameter sin 2 beta using the CBF Detector at Fermilab. The entire run I data sample of 110 pb(-1) of proton-antiproton collisions at root s =1.8 TeV is used to identify a signal sample of similar to 400 B-->J/psi K-S(o) events, where J/psi --> mu(+)mu(-) and K-S(o) - pi(+) pi(-). 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 2 beta=0.79(-0.44)(+0.41)(stat + syst). This value of sin 2 beta is consistent with the standard model prediction, based upon existing measurements, of a large positive CP-violating asymmetry in this decay mode.