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Related papers: Extraction of |Vub| with Reduced Dependence on Sha…

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The use of inclusive B decays to determine |V_{ub}|, |V_{cb}|, m_b and heavy quark matrix elements via spectral moments is discussed.

High Energy Physics - Phenomenology · Physics 2007-05-23 Michael Luke

We present partial branching fractions for inclusive charmless semileptonic B decays Bbar --> X_u ell nubar, and the determination of the CKM matrix element |V_{ub}|. The analysis is based on a sample of 383 million Y(4S) decays into B Bbar…

High Energy Physics - Experiment · Physics 2010-04-12 The BABAR Collaboration , B. Aubert et al

We extract the Cabibbo-Kobayashi-Maskawa matrix element $V_{cb}$ from the exclusive decays of $\Lambda_b\to \Lambda_c\ell\bar \nu_\ell$ and $\Lambda_b\to \Lambda_c M_{(c)}$ with $M=(\pi^-,K^-)$ and $M_c=(D^-,D^-_s)$, where the branching…

High Energy Physics - Phenomenology · Physics 2017-11-02 Y. K. Hsiao , C. Q. Geng

I report results from the CLEO collaboration on semileptonic B decays, highlighting measurements of the Cabibbo-Kobayashi-Maskawa matrix elements Vcb and Vub. I describe the techniques used to obtain the recent improvements in precision for…

High Energy Physics - Experiment · Physics 2019-08-14 Karl M. Ecklund

By analyzing B -> X_u l nu_l spectra with a model based on soft-gluon resummation and an analytic time-like QCD coupling, we obtain |V_ub| = (3.76 +-0.13 +- 0.22)*10^(-3), where the first and the second error refers to experimental and…

High Energy Physics - Phenomenology · Physics 2009-09-27 Ugo Aglietti , Francesca Di Lodovico , Giancarlo Ferrera , Giulia Ricciardi

We present a QCD-based approach to the endpoint region of the lepton spectrum in $\bar B\to X_u\,\ell\,\bar\nu$ decays. We introduce a genuinely nonperturbative form factor, the shape function, which describes the fall-off of the spectrum…

High Energy Physics - Phenomenology · Physics 2010-11-01 Matthias Neubert

We calculate the subleading twist contributions to the endpoint of the inclusive lepton energy spectrum in B -> X_u l \nu. We show that the same two subleading twist functions that appear in the decay B -> X_s \gamma govern the subleading…

High Energy Physics - Phenomenology · Physics 2011-02-01 Christian W. Bauer , Michael Luke , Thomas Mannel

We propose the determination of the CKM matrix element $|V_{ub}|$ by the measurement of the spectrum of $B \to D_s^+ X_u$, dominated by the spectator quark model mechanism $\bar{b} \to D_s^{(*)+} \bar{u}$. The interest of considering $B \to…

High Energy Physics - Phenomenology · Physics 2014-11-17 R. Aleksan , M. Zito , A. Le Yaouanc , L. Oliver , O. Pene , J. -C. Raynal

Measuring the photon energy spectrum in radiative B decays provides essential help for gaining theoretical control over semileptonic B transitions. The hadronic recoil mass distribution in B -> X_u \ell\nu promises the best environment for…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ikaros Bigi , Nikolai Uraltsev

The inclusive direct and cascade semileptonic branching ratios of the b quark were measured from a fit to the lepton momentum spectrum in the B-hadron rest frame, exploiting the charge correlation between the lepton and the heavy meson. The…

High Energy Physics - Experiment · Physics 2007-05-23 Martino Margoni

This proceeding summarizes recent measurements of the Cabibbo-Kobayashi-Maskawa (CKM) matrix elements $|V_{cb}|$ and $|V_{ub}|$ at the Belle and Belle~II experiments. It provides insights derived from both exclusive and inclusive…

High Energy Physics - Experiment · Physics 2023-11-02 Lu Cao

The semileptonic B-> Xu l nu decays allow a pretty clean determination of the CKM matrix element |Vub|. Nevertheless, the presence of weak-annihilation effects near the end-point of the q2 spectrum introduces uncertainties in the inclusive…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. J. Sanz-Cillero

We use the exclusive baryonic $B$ decays to determine the Cabibbo-Kobayashi-Maskawa (CKM) matrix element $V_{ub}$. From the relation $|V_{ub}|^2/|V_{cb}|^2=({\cal B}_\pi/{\cal B}_D){\cal R}_{ff}$ based on $B^-\to p\bar p \pi^-$ and $\bar…

High Energy Physics - Phenomenology · Physics 2016-03-23 Y. K. Hsiao , C. Q. Geng

We calculate the electron spectrum of semileptonic decays of B-mesons into non-charmed hadrons. The shape of the spectrum obtained from QCD sum rules is in general agreement with quark model calculations. At high electron energies the…

High Energy Physics - Phenomenology · Physics 2008-11-26 P. Ball , V. M. Braun , H. G. Dosch

We present the measurements of the CKM matrix parameters Vub, Vcb and of the B mixing oscillation frequency with the BaBar experiment at the asymmetric B-factory PEPII. Data were collected in the years 2000-2002 and the total available…

High Energy Physics - Experiment · Physics 2007-05-23 Daniele del Re

The CLEO Collaboration has extracted improved values of |V_cb| and |V_ub| from measurements of exclusive and inclusive decays of B mesons. The measurement of B -> D* ell nu at zero recoil combined with the predicted form factor F_D*(w_min)…

High Energy Physics - Experiment · Physics 2007-05-23 Stephen P. Pappas

We report a measurement of the inclusive charmless semileptonic branching fraction of B mesons in a sample of 89 million BBbar events recorded with the BABAR detector at the Y(4S) resonance. Events are selected by fully reconstructing the…

High Energy Physics - Experiment · Physics 2008-11-26 B. Aubert

Inclusive bottom hadron decays are analyzed based on the heavy quark effective field theory (HQEFT). Special attentions in this paper are paid to the b\to u transitions and nonspectator effects. As a consequence, the CKM quark mixing matrix…

High Energy Physics - Phenomenology · Physics 2015-06-25 Y. L. Wu , Y. A. Yan

In order to extract some information on the CKM matrix element |Vcb|, we have to determine form factors in B decays. For this, we show that it is relevant to consider the non-forward amplitude between the heavy-light B and D mesons within…

High Energy Physics - Phenomenology · Physics 2007-05-23 F. Jugeau

We present a fit to measured moments of inclusive distributions in B->Xc lv and B-> Xs gamma decays to extract values for the CKM matrix element |Vcb|, the b- and c-quark masses, and higher order parameters that appear in the Heavy Quark…

High Energy Physics - Phenomenology · Physics 2009-06-12 Oliver Buchmueller , Henning Flaecher