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相关论文: On Extracting Heavy Quark Parameters from Moments …

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Photon energy moments in B -> X_s+\gamma and the impact of experimental cuts are analyzed, including the biases exponential in the effective hardness missed in the conventional OPE. We incorporate the perturbative corrections fully…

高能物理 - 唯象学 · 物理学 2008-11-26 D. Benson , I. I. Bigi , N. Uraltsev

We report the OPE-based predictions for a number of lepton energy and hadronic mass moments in the inclusive semileptonic B -> X_c \ell\nu decays with a lower cut on the charged lepton energy. We rely on the direct OPE approach where no…

高能物理 - 唯象学 · 物理学 2014-11-17 Paolo Gambino , Nikolai Uraltsev

Aspects of the OPE-based QCD theory of B decays are discussed. We have at least one nontrivial precision check of the OPE at the nonperturbative level in inclusive decays. The data suggest proximity to the `BPS' limit for B mesons. Its…

高能物理 - 唯象学 · 物理学 2010-11-23 Nikolai Uraltsev

Based on a new, exact QCD factorization formula for the partial B->X_s+gamma decay rate with a restriction on large photon energy, improved predictions are presented for the partial moments <E_gamma> and <E_gamma^2>-<E_gamma>^2 of the…

高能物理 - 唯象学 · 物理学 2009-11-11 Matthias Neubert

We derive the dominant part of the O(\alpha_s^2) correction to the photon energy spectrum in the inclusive decay B-> X_s+gamma. The detailed knowledge of the spectrum is important for relating the theoretical calculations of the B-> X_s +…

高能物理 - 唯象学 · 物理学 2011-01-27 Kirill Melnikov , Alexander Mitov

Moments of the photon energy spectrum in B -> Xs gamma decays, of the hadronic mass spectrum and of the lepton energy spectrum in B -> Xc l nu decays are sensitive to the masses of the heavy quarks as well as to the non-perturbative…

高能物理 - 实验 · 物理学 2007-05-23 Marta Calvi

We have calculated the perturbative corrections to all the structure functions in the semileptonic decays of a heavy quark. Assuming an arbitrary gluon mass as a technical tool allowed to obtain in parallel all the BLM corrections. We…

高能物理 - 唯象学 · 物理学 2008-11-26 Nikolai Uraltsev

A theoretical analysis of the partial inclusive B-->X_s gamma decay rate with a cut E_gamma>E_0 on photon energy must deal with short-distance contributions associated with three different mass scales: the hard scale m_b, an intermediate…

高能物理 - 唯象学 · 物理学 2009-11-11 Thomas Becher , Matthias Neubert

The moments of the photon spectrum in the inclusive $B\to X_s\,\gamma$ decay can be calculated to order $\alpha_s$ accuracy at present, without knowing the $\alpha_s$ corrections to the effective Hamiltonian. We discuss the standard model…

高能物理 - 唯象学 · 物理学 2009-10-28 Anton Kapustin , Zoltan Ligeti

It is argued that the quark mass difference $m_b-m_c$ can be extracted with a high accuracy from experimental data on ratia of moments of lepton energy spectrum in semileptonic decays of $B$ mesons. Theoretical expressions for the moments…

高能物理 - 唯象学 · 物理学 2011-01-25 Mikhail Voloshin

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…

高能物理 - 唯象学 · 物理学 2007-05-23 Giovanni Ossola

A new class of enhanced non-perturbative corrections to the inclusive B->X_s+gamma decay rate is identified, which contribute first at order Lambda/m_b in the heavy-quark expansion and cannot be described using a local operator product…

高能物理 - 唯象学 · 物理学 2008-11-26 Seung J. Lee , Matthias Neubert , Gil Paz

We derive a new parton-like formula, which establishes a simple connection between the electroweak decay rate $\Gamma (\bar B \to X_s\gamma$) and the rate of a free b-quark decay. The main features of our approach are the treatment of the…

高能物理 - 唯象学 · 物理学 2009-10-31 Y. -Y. Keum , P. Yu. Kulikov , I. M. Narodetskii , H. S. Song

We extract the heavy quark masses and non-perturbative parameters from the Delphi preliminary measurements of the first three moments of the charged lepton energy and hadronic mass distributions in semileptonic B decays, using a…

高能物理 - 唯象学 · 物理学 2011-01-25 M. Battaglia , M. Calvi , P. Gambino , A. Oyanguren , P. Roudeau , L. Salmi , J. Salt , A. Stocchi , N. Uraltsev

The nonperturbative contribution, suppressed by powers of the charm quark mass m_c, in the inclusive decay B -> X_s photon is analyzed in the context of heavy quark effective field theory (HQEFT). According to previous analyses, the leading…

高能物理 - 唯象学 · 物理学 2009-10-31 Junegone Chay

We present a detailed evaluation of the total semileptonic B meson width in terms of |V_{cb}| and heavy quark parameters (quark masses and the expectation values of local heavy quark operators). Special attention is given to perturbative…

高能物理 - 唯象学 · 物理学 2010-11-23 D. Benson , I. I. Bigi , Th. Mannel , N. Uraltsev

Strong interactions are addressed in connection to extracting |V_{cb}| and determining heavy quark parameters. A comprehensive approach allows a robust analysis not relying on a 1/m_c expansion; a percent defendable accuracy in |V_{cb}|…

高能物理 - 唯象学 · 物理学 2010-11-23 Nikolai Uraltsev

We present ``state-of-the-art'' theoretical expressions for the triple differential B->X_u l^- nu decay rate and for the B->X_s gamma photon spectrum, which incorporate all known contributions and smoothly interpolate between the…

高能物理 - 唯象学 · 物理学 2010-11-23 Bjorn O. Lange , Matthias Neubert , Gil Paz

Using results on soft-collinear factorization for inclusive B-meson decay distributions, a systematic study of the partial $B\to X_s\gamma$ decay rate with a cut $E_\gamma > E_0$ on photon energy is performed. For values of $E_0$ below…

高能物理 - 唯象学 · 物理学 2009-11-10 Matthias Neubert

We compute the first two moments of the final hadronic invariant mass in inclusive semileptonic B decay, in the presence of a cut on the charged lepton energy. These moments may be measured directly by experiments at the Upsilon(4S) using…

高能物理 - 唯象学 · 物理学 2014-11-17 Adam F. Falk , Michael Luke
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