相关论文: Precision determination of |V_{ub}| from inclusive…
We review how to determine |Vub| from inclusive semileptonic B decay using combined cuts on the leptonic and hadronic invariant masses to eliminate the b -> c background. This leads to a determination of |Vub| with theoretical uncertainty…
We reduce the perturbative uncertainty in the determination of |V_{ub}| from inclusive semileptonic B decays by calculating the rate of B -> X_u l nu events with dilepton invariant mass q^2>(M_B-M_D)^2 at subleading order in the hybrid…
Bauer, Ligeti and Luke have recently proposed a new method for measuring |V_{ub}| in inclusive semileptonic B decays, using a cut on the lepton invariant mass to discriminate against b->c transitions. We investigate the structure of the…
Precision tests of the CKM mechanism and searches for new physics in the flavour sector require dedicated QCD calculations of decay widths and spectra. Significant progress has been achieved in recent years in computing inclusive B decay…
The hadronic mass distribution in semileptonic B-meson decays can be used for extracting the charmless part and thus determining the |V_ub/V_cb| ratio. We take into account first-order perturbative as well as non-perturbative QCD…
We report two novel determinations of |Vub| with reduced model dependence, based on measurements of the mass distribution of the hadronic system in semileptonic B decays. Events are selected by fully reconstructing the decay of one B meson…
The last two years have seen an impressive improvement in the determination of $|V_{ub}|$, especially from inclusive decays. The error on $|V_{ub}|$ measured with inclusive decays was reduced from 18% (PDG 2004) to 8% (PDG 2006). This…
We make an analysis of the hadronic invariant mass spectrum in inclusive charmless semileptonic B meson decays in a QCD-based approach. The decay width is studied as a function of the invariant mass cut. We examine their sensitivities to…
Recent advances in improving extractions of |Vcb| and m_b from spectra of semileptonic inclusive B decay are reported. Results of a general moment analysis of the lepton energy spectrum and the hadronic invariant mass spectrum are…
The determinations of |V_{cb}| and |V_{ub}| from inclusive semileptonic B decays are reviewed. A comparison of the light-cone approach with the heavy quark expansion approach is made. The perspective for further improvement of the |V_{cb}|…
In light of the large amount of new experimental data, we revisit the determination of V_{cb} and m_b from inclusive semileptonic and radiative B decays. We study shape variables to order lqcd^3/m_b^3 and alpha_s^2\beta_0, and include the…
We report on the determination of $|V_{cb}|$ from the comparison of the semileptonic inclusive decay rates of B-- and D--mesons using the heavy quark symmetry of QCD. While the renormalization scale ambiguity does not allow for a reliable…
Following a strategy introduced earlier by the authors, we show that it is possible to extract |V_{ub}| from the cut hadronic mass spectrum of B decays without large systematic errors which usually arise from having to model the Fermi…
In order to determine the ratio of CKM matrix elements |V_{ub}/V_{cb}| (and |V_{ub}|), we propose a new model-independent method based on the heavy quark effective theory, which is theoretically described by the phase space factor and the…
We present OPE predictions for the hadronic mass and q^2 moments in inclusive semileptonic charmless B decays, with a lower cut on the charged lepton energy and an upper cut on the hadronic invariant mass. We include non-perturbative…
We calculate the hadronic tensor for inclusive semileptonic B decay to O(alpha_s). This allows O(alpha_s Lambda_{QCD}/mb) corrections to hadronic invariant mass observables to be directly evaluated with experimentally required cuts on phase…
The prospects for a precise and model independent determination of $|V_{ub}|$ from inclusive and exclusive semileptonic B decays are reviewed.
We determine $|V_{cb}|$ from inclusive semileptonic B decays including resummation of supposedly large perturbative corrections, which originate from the running of the strong coupling. We argue that the low value of the BLM scale found…
The hadronic invariant mass spectrum for the inclusive charmless semileptonic decay $B\to X_u e \bar\nu_e$ is studied. Particular attention is paid to the region $s_H<m_D^2$, which may be useful for extracting the value of $|V_{ub}|$. The…
Methods are described in the framework of light-cone expansion which allow one to determine the Cabibbo-Kobayashi-Maskawa matrix elements |V_ub| and |V_cb| from measurements of the differential decay rates as a function of the scaling…