We present results for the moments of observed spectra in inclusive semileptonic B-meson decays to charm hadrons B̅ →Xcℓ-ν̅ . Moments of the hadronic-mass and the combined mass-and-energy spectra for different minimum electron or muon momenta between 0.8 and 1.9 GeV/c are obtained from a sample of 232×106 Υ(4S)→BB̅ events, collected with the BABAR detector at the PEP-II asymmetric-energy B-meson factory at SLAC. We also present a reevaluation of the moments of electron-energy spectra and partial decay fractions B(B̅ →Xce-ν̅ ) for minimum electron momenta between 0.6 and 1.5 GeV/c based on a sample of 51×106 Υ(4S)→BB̅ events. The measurements are used for the extraction of the total decay fraction, the Cabibbo-Kobayashi-Maskawa (CKM) matrix element |Vcb|, the quark masses mb and mc, and four heavy-quark QCD parameters in the framework of a Heavy-Quark Expansion (HQE). We find B(B̅ →Xcℓ-ν̅ )=(10.64±0.17±0.06)% and |Vcb|=(42.05±0.45±0.70)×10-3.
Measurement and interpretation of moments in inclusive semileptonic decays B̅ →Xcℓ-ν̅
PERUZZI, Ida Marena;BIASINI, Maurizio
2010
Abstract
We present results for the moments of observed spectra in inclusive semileptonic B-meson decays to charm hadrons B̅ →Xcℓ-ν̅ . Moments of the hadronic-mass and the combined mass-and-energy spectra for different minimum electron or muon momenta between 0.8 and 1.9 GeV/c are obtained from a sample of 232×106 Υ(4S)→BB̅ events, collected with the BABAR detector at the PEP-II asymmetric-energy B-meson factory at SLAC. We also present a reevaluation of the moments of electron-energy spectra and partial decay fractions B(B̅ →Xce-ν̅ ) for minimum electron momenta between 0.6 and 1.5 GeV/c based on a sample of 51×106 Υ(4S)→BB̅ events. The measurements are used for the extraction of the total decay fraction, the Cabibbo-Kobayashi-Maskawa (CKM) matrix element |Vcb|, the quark masses mb and mc, and four heavy-quark QCD parameters in the framework of a Heavy-Quark Expansion (HQE). We find B(B̅ →Xcℓ-ν̅ )=(10.64±0.17±0.06)% and |Vcb|=(42.05±0.45±0.70)×10-3.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.