Update, Lifetime Difference and Mixing Phase

In this paper we review the results of untagged decays from the CDF and DØ detectors at Fermilab, using integrated luminosities of 260 pb−1 and 1.0 fb−1, respectively. Through a study of the time-dependent angular distributions of the decay products of the J/ψ and ϕ mesons, the even and odd CP components of the decay are separated, and thus the lifetime difference and the CP violating phase are measured. The results are consistent with Standard Model predictions within the measurement uncertainties.