Improved measurement of Vub with inclusive semileptonic B decays

Phys Rev Lett. 2002 Jun 10;88(23):231803. doi: 10.1103/PhysRevLett.88.231803. Epub 2002 May 28.

Abstract

We report a new measurement of the Cabibbo-Kobayashi-Maskawa parameter Vub made with a sample of 9.7 x 10(6) BB- events collected with the CLEO II detector. Using heavy quark theory, we combine the observed yield of leptons from semileptonic B decay in the end-point momentum interval 2.2-2.6 GeV/c with recent CLEO II data on B-->X(s)gamma to find Vub = (4.08+/-0.34+/-0.44+/-0.16+/-0.24)x10(-3), where the first two uncertainties are experimental and the last two are from theory.