By analyzing B → Xuℓνℓ spectra with a model based on soft–gluon resummation and an analytic time–like QCD coupling, we obtain |Vub | = (3.76 ± 0.13 ± 0.22) × 10 −3, where the first and the second error refers to experimental and theoretical errors, respectively. This model successfully describes the accurate experimental data in beauty fragmentation, which has similar soft-gluon effects. The |Vub | value is obtained from the available measured semileptonic branching fractions in limited regions of the phase–space. The distributions in the lepton energy Eℓ, the hadron invariant mass mX, the light–cone momentum P+ ≡ EX − |pX|, together with the double distributions in (mX,q 2) and (Eℓ,smax h), are used to select the phase–space regions. The q2 is the dilepton squared momentum and smax h is the maximal m2 X at fixed q2 and Eℓ. The |Vub | value obtained is in complete agreement with the value coming from exclusive B decays and from an over–all fit to the Standard Model parameters. We show that th
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