Search for Bs Mixing with Inclusive Leptons at SLD

We have performed a sensitive search for Bs0 - (bar B)s0 mixing using a sample of 400,000 hadronic Z0 decays collected by the SLD experiment at the SLC between 1996 and 1998. Bs0 and (bar B)s0 events were produced by Z0 → b(bar b) decays where each side hadronized independently to b hadrons. The analysis determines the b hadron flavor at production by exploiting the large polarized forward-backward asymmetry of the b quark as well as information from the hemisphere opposite that of the reconstructed B decay. The final state b quark flavor is determined by the charge of a high pT lepton. A novel, highly efficient vertexing technique has been developed to locate the B decay vertex by exploiting the high pT lepton and the semileptonic decay topology. No significant mixing signal was found and the following ranges of the oscillation frequency of Bs0-(bar B)s0 mixing are excluded at 95% CL from the analysis presented in this thesis: Δms < 1.3 ps-1; 2.0 < Δms < 8.6 ps-1; and 9.8 < Δms < 12.2 ps-1. The gaps extending from 1.3 to 2.0 ps-1 and 8.6 to 12.2 ps-1 are excluded by other analyses. Combining results, Δms < 12.3 ps-1 can be excluded at 95% CL. This limit puts significant constraints on the CKM unitarity triangle