The 2004 UTfit collaboration report on the status of the unitarity triangle in the Standard Model

Using the latest determinations of several theoretical and experimental parameters, we update the Unitarity Triangle analysis in the Standard Model. The basic experimental constraints come from the measurements of vertical bar V-ub/V(cb)vertical bar, Delta m(d), the lower limit on Delta m(s), epsilon K, and the measurement of the phase of the B-d-B-d mixing amplitude through the time-dependent CP asymmetry in B-0 -> J/psi K-0 decays. In addition, we consider the direct determination of alpha,gamma, 2 beta + gamma and cos 2 beta from the measurements of new CP-violating quantities, recently performed at the B factories. We also discuss the opportunities offered by improving the precision of the various physical quantities entering in the determination of the Unitarity Triangle parameters. The results and the plots presented in this paper can also be found at the URL http://www.utfit.org, where they are continuously updated with the newest experimental and theoretical results.