|V cb |, |V ub |, and HQET at CLEO

Abstract

I report results from the CLEO collaboration on semileptonic B decays, highlighting measurements of the Cabibbo-Kobayashi-Maskawa matrix elements |V cb | and |V ub |. I describe the techniques used to obtain the recent improvements in precision for these measurements, including the use of the b→ sγ photon spectrum to reduce hadronic uncertainties in semileptonic B decays. I also report new measurements of |V cb | using the inclusive semileptonic branching fraction ${\cal B}(B\to X e \nu)$ and of |V ub | through study of the q2 dependence of B→πℓν and B→ρℓν. PACS: 12.15.Hh Determination of Kobayashi-Maskawa matrix elements – 13.20.He Decays of bottom mesons