This paper reports an updated measurement of the Standard Model
CP violation parameter sin 2Beta using the CDF Detector at Fermilab. The
entire Run I data sample of 110 pb-1 of proton antiproton collisions at
s**(1/2) = 1.8 TeV is used to identify a signal sample of ~400 B --> J/psiK0(s)
events, where J/psi --> mu+ mu- and K0(s) --> mu+ mu-. The flavor of the
neutral B meson is identified at the time of production by combining
information from three algorithms: a same-side tag, a jet-charge tag, and a
soft-lepton tag. A maximum likelihood fitting method is used to determine
sin 2Beta = 0.79+0.41_-0.44(stat+syst). This value of s 2Beta is
consistent with the Standard Model prediction, based upon existing
measurements, of a large positive CP-violating asymmetry in this decay mode.
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Updated: Thursday, 2001 January 25 08:43:24 CST automatically from input from Carol Picciolo