Determination of |Vub| from Measurements of the Electron and Neutrino Momenta in Inclusive Semileptonic B Decays

Abstract

We present a determination of the Cabibbo-Kobayashi-Maskawa matrix element | V u b | based on the analysis of semileptonic B decays from a sample of 88 × 10 6 Υ ( 4 S ) decays collected with the BABAR detector at the SLAC PEP-II e + e − storage ring. Charmless semileptonic B decays are selected using measurements of the electron energy and the invariant mass squared of the electron-neutrino pair. We obtain | V u b | = ( 3.95 ± 0.26 + 0.58 − 0.42 ± 0.25 ) × 10 − 3 , where the errors represent experimental uncertainties, heavy quark parameter uncertainties, and theoretical uncertainties, respectively.