Determination of |Vub| in inclusive semileptonic B meson decays
  We present a preliminary determination of the CKM matrix element |Vub| based on the analysis of semileptonic B decays from a sample of 88 million Upsilon(4S) decays collected with the BaBar detector at the e+e- storage ring. Charmless semileptonic B decays are selected using the electron energy E_e and the invariant mass q^2 of the electron-neutrino pair. The neutrino momentum is inferred from a measurement of the visible energy and momentum in the detector and knowledge of the e+e- beam momenta. The partial branching fraction is determined in a region of the q^2-E_e plane where semileptonic B decays to charm are highly suppressed. The total charmless semileptonic branching fraction is extracted using a theoretical calculation based on the heavy quark expansion. Preliminary results yield |Vub| = (4.57 +/- 0.21 +/- 0.25 +/- 0.34 +0.59/-0.29 +/- 0.22) x 10^{-3} where the uncertainties are from statistics (data and MC), detector modeling, background modeling, the shape function, and the heavy quark operator product expansion, respectively. 
B. Aubert, et al, The BaBar Collaboration