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Related papers: Infrared Corrections to the Top Quark Width

200 papers

Precise predictions for an $e^+e^-\rightarrow t\bar{t}$ cross section are presented at an energy region from 400 GeV to 800 GeV. Cross sections are estimated including the beam-polarization effects with full $\mathcal{O}(\alpha)$, and also…

High Energy Physics - Phenomenology · Physics 2019-07-24 Junpei Fujimoto , Yoshimasa Kurihara , Nhi M. U. Quach

We compute non-perturbatively the average up-down and strange quark masses from the large momentum (short-distance) behaviour of the quark propagator in the Landau gauge. This method, which has never been applied so far, does not require…

High Energy Physics - Lattice · Physics 2009-10-31 Damir Becirevic , Vicente Gimenez , Vittorio Lubicz , Guido Martinelli

Recent CDF and D0 measurements of the top quark forward-backward asymmetry at the Tevatron present deviations between 1-sigma and 2-sigma from QCD predictions and a cut M_inv > 450 GeV on the events increases this deviation to 3.4 sigma in…

High Energy Physics - Phenomenology · Physics 2012-05-29 Davide Pagani

This talk was presented to a non-lattice audience at the June, 1992 Paris Workshop on QCD Vacuum Structure. We report on the status of quark and gluon propagators in quenched, gaugefixed lattice QCD. In Landau gauge we find that the…

High Energy Physics - Lattice · Physics 2007-05-23 Claude Bernard , Amarjit Soni , Ken Yee

We present the first study of the quark mass dependence of the heavy quark momentum and spatial diffusion coefficients using lattice QCD with light dynamical quarks corresponding to a pion mass of 320 MeV. We find that, for the temperature…

Since b quark mass is not asymptotically large, chirally enhanced corrections which arise from twist-3 wave functions may be important in B decays. We thus evaluate the hadronic matrix elements with the final light pseudoscalar mesons…

High Energy Physics - Phenomenology · Physics 2009-11-07 Dongsheng Du , Deshan Yang , Guohuai Zhu

Recently, it has been shown that the concept of the pole mass of a heavy quark becomes ambiguous beyond perturbation theory, because of the presence of infrared renormalons. We argue that the predictions of heavy quark effective theory,…

High Energy Physics - Phenomenology · Physics 2009-10-09 Matthias Neubert , Chris T. Sachrajda

In this paper I investigate the analytic properties of the quark propagator Dyson-Schwinger equation (DSE) in the Landau gauge. In the quark self-energy, the combined gluon propagator and quark-gluon vertex is modeled by an effective…

High Energy Physics - Phenomenology · Physics 2017-04-26 Andreas Windisch

We study effects of the heavy top quark ($m_t \approx 180 GeV$) on the scalar sector of the minimal Standard Model. We construct the effective potential for the scalar doublet, by first taking into account the leading contributions of the…

High Energy Physics - Phenomenology · Physics 2011-01-13 G. Cvetic

We study the impact on chiral symmetry breaking of a recently developed model for the QCD analytic invariant charge. This charge contains no adjustable parameters, other than the QCD mass scale $\Lambda$, and embodies asymptotic freedom and…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. C. Aguilar , A. V. Nesterenko , J. Papavassiliou

The Standard Model (SM) prediction of the top quark forward backward asymmetry is shown to be slightly enhanced by a correction factor of 1.05 due to electroweak Sudakov (EWS) logarithms of the form (\alpha/sin^2 \theta_W)^n log^{m< 2n}…

High Energy Physics - Phenomenology · Physics 2015-06-03 Aneesh V. Manohar , Michael Trott

We study the phase diagram of strongly interacting matter with light quarks using a recently proposed, small parameter approach to infrared QCD in the Landau gauge. This is based on an expansion with respect to both the inverse number of…

High Energy Physics - Theory · Physics 2020-02-05 Jan Maelger , Urko Reinosa , Julien Serreau

We determine the strange quark condensate from lattice QCD for the first time and compare its value to that of the light quark and chiral condensates. The results come from a direct calculation of the expectation value of the trace of the…

High Energy Physics - Lattice · Physics 2013-03-14 C. McNeile , A. Bazavov , C. T. H. Davies , R. J. Dowdall , K. Hornbostel , G. P. Lepage , H. D. Trottier

Infrared finite solutions for the gluon propagator of pure QCD are obtained from the gauge-invariant non-linear Schwinger-Dyson equation formulated in the Feynman gauge of the background field method. These solutions may be fitted using a…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. C. Aguilar , J. Papavassiliou

Light scalar top quarks with a small mass difference with respect to the neutralino mass are of particular cosmological interest. This study uses an Iterative Discriminant Analysis method to optimize the expected selection efficiency at a…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Sopczak , A. Finch , A. Freitas , C. Milstene , M. Schmitt

We compute the renormalized Dirac spectral density in $N_f = 2+1$ QCD at physical quark masses, temperature $T = 230$ MeV and system size $L_s = 3.4$ fm. To that end, we perform a point-wise continuum limit of the staggered density in…

High Energy Physics - Lattice · Physics 2024-10-28 Andrei Alexandru , Claudio Bonanno , Massimo D'Elia , Ivan Horváth

A completely non-perturbative estimate is given for the u/d and strange quark masses in quenched QCD using O(a) improved fermions and, for comparison, Wilson fermions. For improved fermions we find m_{u/d}^MSbar(\mu=2 GeV) = 4.4(2) MeV,…

High Energy Physics - Lattice · Physics 2015-06-25 M. Gockeler , R. Horsley , B. Klaus , W. Kurzinger , H. Oelrich , D. Petters , D. Pleiter , P. E. L. Rakow , G. Schierholz , P. Stephenson

A simulation of quenched QCD with the overlap Dirac operator has been completed using 100 Wilson gauge configurations at beta = 6 on an 18^3 x 64 lattice and at beta = 5.85 on a 14^3 x 48 lattice, both in Landau gauge. We present results…

We fix exactly and uniquely the infrared structure of the full gluon propagator in QCD, not solving explicitly the corresponding dynamical equation of motion. By construction, this structure is an infinite sum over all possible severe…

High Energy Physics - Phenomenology · Physics 2009-11-10 V. Gogohia

We derive the QCD corrections to the electroweak gauge bosons vacuum polarization functions at high and zero--momentum transfer in the case of arbitrary internal quark masses. We then discuss in this general case (i) the connection between…

High Energy Physics - Phenomenology · Physics 2009-10-22 A. Djouadi , P. Gambino