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The shape function of $B$-meson defined in heavy quark effective theory (HQET) plays a crucial role in the analysis of inclusive $B$ decays, and constitutes one of the dominant uncertainties in the determination of CKM matrix element…

高能物理 - 唯象学 · 物理学 2025-04-30 Wei Wang , Ji Xu , Qi-An Zhang , Shuai Zhao

The values of two important parameters of the heavy quark effective theory,\, $\bar \Lambda$ and $\mu_\pi^2$ (the mean value of the heavy quark three momentum squared),\, have been determined recently in \cite {GKLW} from the precise CLEO…

高能物理 - 唯象学 · 物理学 2009-10-28 Victor Chernyak

We consider HQET including the first order correction in 1/m. A strategy for the computation of the b-quark mass is discussed. Only two quantities Phi_1/2 have to be considered in order to match QCD and HQET, since the spin-dependent…

高能物理 - 格点 · 物理学 2007-05-23 Michele Della Morte , Nicolas Garron , Rainer Sommer , Mauro Papinutto

We compute the mass of the b-quark and the B_s meson decay constant in quenched lattice QCD using a combination of HQET and the standard relativistic QCD Lagrangian. We start from a small volume, where one can directly deal with the…

高能物理 - 格点 · 物理学 2011-01-27 Damiano Guazzini , Rainer Sommer , Nazario Tantalo

B meson semileptonic decays are a crucial tool in our studies of the quark mixing parameters Vcb and Vub. The interplay between experimental and theoretical challenges to achieve precision in the determination of these fundamental…

高能物理 - 唯象学 · 物理学 2014-11-17 Marina Artuso

We consider electroweak corrections to the relation between the running $\overline{\mathrm{MS}}$ mass $m_b$ of the $b$ quark in the five-flavor QCD$\times$QED effective theory and its counterpart in the Standard Model (SM). As a bridge…

高能物理 - 唯象学 · 物理学 2018-09-26 A. V. Bednyakov , B. A. Kniehl , A. F. Pikelner , O. L. Veretin

Masses and decay constants of mesons containing a single $c$ or $b$ quark are described within the framework of heavy-quark symmetry. The $B_s^* - B_s$ and $\bar B^{*0} - \bar B^0$ mass splittings are found equal to within a fraction of an…

高能物理 - 唯象学 · 物理学 2007-05-23 Jonathan L. Rosner

We derive the strange quark transverse momentum distribution for the $% b\to s\gamma $ decay. A resummed formula is presented showing the singularity structure in the impact parameter $b$. We observe the appearance of a new next-to-leading…

高能物理 - 唯象学 · 物理学 2007-05-23 Roberto Sghedoni

The important parameter \mu_G^2 of the heavy quark expansion is analyzed including perturbative and power corrections. It is found that \mu_G^2(2GeV) is known with a few percent accuracy. The perturbative corrections are computed and found…

高能物理 - 唯象学 · 物理学 2009-11-07 Nikolai Uraltsev

The moments of the heavy quark-parton distribution functions in a heavy pseudoscalar meson are calculated from QCD sum rules. Expanding these sum rules in the inverse heavy quark mass we obtain the heavy-mass limits of the moments.…

高能物理 - 唯象学 · 物理学 2011-06-02 A. G. Oganesian

The interaction potential V(Q^2) between static test charges can be used to define an effective charge $\alpha_V(Q^2)$ and a physically-based renormalization scheme for quantum chromodynamics and other gauge theories. In this paper we use…

高能物理 - 唯象学 · 物理学 2009-09-11 Stanley J. Brodsky , Michael Melles , Johan Rathsman

We point out that applying the photon energy cut significantly modifies the moments of energy spectrum in B->X_s+gamma decays, with a certain class of effects not accounted for in the mostly used OPE expressions. This leads to a systematic…

高能物理 - 唯象学 · 物理学 2010-04-05 I. I. Bigi , N. Uraltsev

Exploiting recently proposed novel improvements of the techniques used for extracting from QCD sum rules pivotal hadron characteristics, including their systematic errors, we succeed to achieve a conspicuous agreement of the predictions of…

高能物理 - 唯象学 · 物理学 2014-04-15 Wolfgang Lucha , Dmitri Melikhov , Silvano Simula

We compute the exact two-loop matching coefficients for the strong coupling constant alpha_s and the bottom-quark mass m_b within the Minimal Supersymmetric Standard Model (MSSM), taking into account O(alpha_s^2) contributions from…

高能物理 - 唯象学 · 物理学 2010-04-15 A. Bauer , L. Mihaila , J. Salomon

We measured two moments of the lepton momentum spectrum in B -> X l nu, where l= e or mu, for p_l > 1.5 GeV/c. From these we derive the Heavy Quark Expansion (HQE) parameters Lambda-bar(MS-bar) = 0.39 +- 0.03(stat) +- 0.06(sys) +- 0.12(th)…

高能物理 - 实验 · 物理学 2007-05-23 R. A. Briere

The contributions of subleading shape functions to inclusive decay distributions of B mesons are derived from a systematic two-step matching of QCD current correlators onto soft-collinear and heavy-quark effective theory. At tree-level, the…

高能物理 - 唯象学 · 物理学 2010-02-03 Stefan W. Bosch , Matthias Neubert , Gil Paz

The fully heavy axial-vector diquark-antidiquark structures $bb\overline{c} \overline{c}$ are explored by means of the QCD sum rule method. They are modeled as four-quark mesons $T_{\mathrm{1}}$ and $T_{\mathrm{2}}$ composed of…

高能物理 - 唯象学 · 物理学 2024-03-13 S. S. Agaev , K. Azizi , H. Sundu

B meson rare decays ($B\to K(K^{*})l\bar l$ and $B\to K^*\gamma$) are analyzed in the framework of effective field theory of heavy quarks. The semileptonic and penguin type form factors for these decays are calculated by using the light…

高能物理 - 唯象学 · 物理学 2014-11-17 M. Zhong , Y. L. Wu , W. Y. Wang

Precision determinations of the top-quark mass require theory predictions with a well-defined mass parameter in a given renormalization scheme. The top-quark's running mass in the MSbar scheme can be extracted with good precision from the…

高能物理 - 唯象学 · 物理学 2014-08-27 S. Moch

The comparison between parameterisations of the perturbation results for the decay width of the Standard Model Higgs boson to \bar{b}b-quarks pairs, based on application of \bar{MS}-scheme running quark mass and pole b-quark mass, are…

高能物理 - 唯象学 · 物理学 2007-12-23 A. L. Kataev , V. T. Kim