| Izvleček: | Moments of the hadronic invariant mass and of the lepton energy spectra in semileptonic B decays have been determined with the data recorded by the DELPHI detector at LEP. From measurements of the inclusive b-hadron semileptonic decays, and imposing constraints from other measurements on b- and c-quark masses, the first three moments of the lepton energy distribution and of the hadronic mass distribution, have been used to determine parameters which enter into the extraction of |Vcb| from the measurement of the inclusive b-hadron semileptonic decay width. The values obtained in the kinetic scheme are: mb(1 GeV) = 4.591 ± 0.062 ± 0.039 ± 0.005 GeV/c2, mc(1 GeV) = 1.170 ± 0.093 ± 0.055 ± 0.005 GeV/c2, μπ2(1 GeV) = 0.399 ± 0.048 ± 0.034 ± 0.087 GeV2, ∂̃D3 = 0.053 ± 0.017 ± 0.011 ± 0.026 GeV3, and include corrections at order 1/m b3, Using these results, and present measurements of the inclusive semileptonic decay partial width of b-hadrons at LEP, an accurate determination of |Vcb| is obtained: |Vcb| = 0.0421 × (1 ± 0.014meas. ± 0.014flt ± 0.015th.).
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