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Related papers: Scheme variations of the QCD coupling

200 papers

Previously developed Pade-related method of resummation for QCD observables, which achieves exact renormalization-scale-invariance, is extended so that the scheme-invariance is obtained as well. The dependence on the leading scheme…

High Energy Physics - Phenomenology · Physics 2009-10-31 G. Cvetic

We compute the Standard Model scalar coupling ($\lambda$) evolution in a particular QCD resummation scheme, where the QCD coupling becomes infrared finite due to the presence of a dynamically generated gluon mass, leading to the existence…

High Energy Physics - Phenomenology · Physics 2015-06-17 J. D. Gomez , A. A. Natale

We discuss our present knowledge of $\alpha_s$, the fundamental running coupling or effective charge of Quantum Chromodynamics (QCD). A precise understanding of the running of $\alpha_s(Q^2) $ at high momentum transfer, $Q$, is necessary…

High Energy Physics - Phenomenology · Physics 2023-12-04 A. Deur , S. J. Brodsky , C. D. Roberts

A particular choice of renormalization, within the simplifications provided by the non-perturbative property of Effective Locality, leads to a completely finite, renormalized theory of QCD, in which all correlation functions can, in…

High Energy Physics - Theory · Physics 2015-05-20 H. M. Fried , P. H. Tsang , Y. Gabellini , T. Grandou , Y. -M. Sheu

The problem of improving the reliability of perturbative QCD predictions at moderate energies is considered. These predictions suffer from substantial renormalization scheme dependence, which is illustrated using as an example the QCD…

High Energy Physics - Phenomenology · Physics 2007-05-23 Piotr A. Raczka

In this work the determination of low-energy bound states in Quantum Chromodynamics is recast so that it is linked to a weak-coupling problem. This allows one to approach the solution with the same techniques which solve Quantum…

High Energy Physics - Theory · Physics 2009-10-28 K. G. Wilson , T. Walhout , A. Harindranath , W. M. Zhang , R. J. Perry , S. Glazek

In this talk we introduce the main features of a QCD-based model in which the coupling $\alpha_{s}$ is constrained by an infrared mass scale. We show recent applications of this model to hadron-hadron collisions, gap survival probability…

High Energy Physics - Phenomenology · Physics 2011-05-12 E. G. S. Luna

As an elaboration of the analytic approach to Quantum Chromodynamics (QCD), a new model for the QCD analytic running coupling is proposed. A self-evident advantage of the new analytic running coupling (NARC) is that it incorporates the…

High Energy Physics - Phenomenology · Physics 2017-08-23 A. V. Nesterenko

Quantum Chromodynamics is an established part of the Standard Model and an essential part of the toolkit for searching for new physics at high-energy colliders. I present a status report on the theory of QCD and review some of the important…

High Energy Physics - Phenomenology · Physics 2009-11-10 W. J. Stirling

The QCD coupling, $\alpha_s$, has a critical role in Hadron collider studies of the Standard Model Effective Field Theory (SMEFT). Patterns of measurements can be modified by local contact operators in the SMEFT that change the measured…

High Energy Physics - Phenomenology · Physics 2023-06-27 Michael Trott

Bottom-up holographic models of QCD, inspired by the AdS/CFT correspondence, have shown a remarkable degree of phenomenological success. However, they rely on a number of bold assumptions. We investigate the reliability of one of the key…

High Energy Physics - Phenomenology · Physics 2010-03-16 Aleksey Cherman , Thomas D. Cohen , Elizabeth S. Werbos

Conformal symmetry provides a systematic approximation to QCD in both its perturbative and nonperturbative domains. One can use the AdS/CFT correspondence between Anti-de Sitter space and conformal gauge theories to obtain an analytically…

High Energy Physics - Phenomenology · Physics 2009-11-13 Stanley J. Brodsky

We review the present knowledge for $\alpha_s$, the fundamental coupling underlying the interactions of quarks and gluons in QCD. The dependence of $\alpha_s(Q^2)$ on momentum transfer $Q$ encodes the underlying dynamics of hadron physics…

High Energy Physics - Phenomenology · Physics 2023-05-05 A. Deur , S. J. Brodsky , G. F. de Teramond

The conventional approach to fixed-order perturbative QCD predictions is based on an arbitrary choice of the renormalization scale, together with an arbitrary range. This {\it ad hoc} assignment of the renormalization scale causes the…

High Energy Physics - Phenomenology · Physics 2019-12-19 Xing-Gang Wu , Jian-Ming Shen , Bo-Lun Du , Xu-Dong Huang , Sheng-Quan Wang , Stanley J. Brodsky

In ${\cal N}=1$ supersymmetric QCD-like theories we derive the (all-order) exact equations relating the renormalization group behaviour of the strong and electromagnetic couplings and prove that they are valid in the HD+MSL renormalization…

High Energy Physics - Theory · Physics 2025-03-04 A. L. Kataev , K. V. Stepanyantz

A key problem in making precise perturbative QCD predictions is the uncertainty in determining the renormalization scale $\mu$ of the running coupling $\alpha_s(\mu^2).$ The purpose of the running coupling in any gauge theory is to sum all…

High Energy Physics - Phenomenology · Physics 2012-10-26 Stanley J. Brodsky , Leonardo Di Giustino

Perturbative QCD (pQCD) running coupling a(Q^2) (=alpha_s(Q^2)/pi) is expected to get modified at low spacelike momenta 0 < Q^2 < 1 GeV^2 so that, instead of having unphysical (Landau) singularities it remains smooth and finite there, due…

High Energy Physics - Phenomenology · Physics 2015-06-17 Gorazd Cvetič

The QCD one-loop renormalization is restudied in a mass-dependent subtraction scheme in which the quark mass is not set to vanish and the renormalization point is chosen to be an arbitrary timelike momentum. The correctness of the…

High Energy Physics - Theory · Physics 2007-05-23 Jun-Chen Su , Lian-You Shan , Ying-Hui Cao

In this contribution to the proceedings, we analyze the transition from perturbative and non- perturbative QCD embedded in the coupling constant. In the study of quark-hadron duality, we suggest that the realization of the latter is related…

High Energy Physics - Phenomenology · Physics 2013-12-04 A. Courtoy

Conformal symmetry is broken in physical QCD; nevertheless, one can use conformal symmetry as a template, systematically correcting for its nonzero $\beta$ function as well as higher-twist effects. For example, commensurate scale relations…

High Energy Physics - Phenomenology · Physics 2017-08-23 Stanley J. Brodsky