Studies of quark mixing with ARGUS

Recent ARGUS results relevant to the determination of the Cabibbo-Kobayashi-Maskawa matrix elements are reviewed. The |Vcb|values of 0.046 ± 0.009, 0.042 ± 0.008, and 0.046 ± 0.005 are obtained from the studies of the B0 → D*- l+ν, B0 → D- l+ν, and B → lνX decays respectively. New data confirm our observation of charmless semileptonic B meson decays. An excess of 52 ± 11 leptons above known backgrounds is now observed beyond the endpoint of the momentum spectrum for B decays via b → c transitions. This signal leads to a model dependent value of about 0.1 for the ratio of the CKM matrix elements |Vub|/|Vcb|. One event with a decay antiB0 → π+ μ- antiν is completely reconstructed. It represents the first direct observation of b → ulν transitions. An indication of non-BantiB decays of Υ(4S) into J/ψX is obtained. A study of B0 antiB0 mixing was performed using an additional 70% more data. The value obtained for the mixing parameter τ = 0.21 ± 0.06 agrees perfectly with the original observation and leads to the limit 0.007 < |Vtd| < 0.034