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Related papers: Scheme variations of the QCD coupling

200 papers

Theoretical predictions for particle production cross sections and decays at colliders rely heavily on perturbative Quantum Chromodynamics (QCD) calculations, expressed as an expansion in powers of the strong coupling constant $\alpha_s$.…

Commensurate scale relations are perturbative QCD predictions which relate observable to observable at fixed relative scale, such as the ``generalized Crewther relation", which connects the Bjorken and Gross-Llewellyn Smith deep inelastic…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. J. Brodsky , J. Rathsman

Inhomogeneous ensembles of quantum dots (QDs) coupled to a charge reservoir are widely studied by using, e.g., electrical methods like capacitance-voltage spectroscopy. We present experimental measurements of the QD capacitance as a…

Light-front coordinates offer a scenario in which a constituent picture of hadron structure can emerge from QCD, after several difficulties are addressed. Field theoretic difficulties force us to introduce cutoffs that violate Lorentz…

High Energy Physics - Theory · Physics 2008-02-03 Robert J. Perry

We analyze two sets of specific functions, that/which form the basis of the nonpower asymptotic expansions both in the timelike and spacelike regions for single scale dependent QCD observables in the Shirkov--Solovtsov's Analytic…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. A. Magradze

Quantum Chromodynamics constitutes the quantum field theory of the strong interaction. Despite the success of this theory in the description of several hadronic processes, the elastic scattering is still a theoretical challenge. This…

High Energy Physics - Phenomenology · Physics 2018-05-29 P. V. R. G. Silva

We propose a general model where quintessence couples to electromagnetism via its kinetic term. This novelty generalizes the linear dependence of the gauge kinetic function on $\phi$, commonly adopted in the literature. The interaction…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-23 Bruno J. Barros , Vitor da Fonseca

We consider the behaviour of open quantum systems in dependence on the coupling to one decay channel by introducing the coupling parameter $\alpha$ being proportional to the average degree of overlapping. Under critical conditions, a…

Quantum Physics · Physics 2009-10-31 C. Jung , M. Mueller , I. Rotter

In addition to the well-known quantum chromodynamical theta angle, we show that the Standard Model has another theta angle which is invariant under arbitrary chiral rotations of quarks and leptons. The new theta angle can be identified with…

High Energy Physics - Phenomenology · Physics 2026-03-25 James Brister , Bingwei Long , Longjie Ran , Muhammad Shahzad , Zheng Sun , Yingpei Zou

Quantum Chromodynamics (QCD), the generally accepted theory for the strong interactions, describes the interactions between quarks and gluons. The strongly interacting particles that are seen in nature are hadrons, which are composites of…

High Energy Physics - Phenomenology · Physics 2018-02-14 Stephen Lars Olsen , Tomasz Skwarnicki , Daria Zieminska

As a basic requirement of the renormalization group invariance, any physical observable must be independent of the choice of both the renormalization scheme and the initial renormalization scale. In this paper, we show that by using the…

High Energy Physics - Phenomenology · Physics 2018-05-30 Xing-Gang Wu , Jian-Ming Shen , Bo-Lun Du , Stanley J. Brodsky

Even though quantum chromodynamics is a broken conformal theory, the AdS/CFT correspondence has led to important insights into the properties of QCD. For example, as shown by Polchinski and Strassler, dimensional counting rules for the…

High Energy Physics - Phenomenology · Physics 2009-09-11 Stanley J. Brodsky , Guy F. de Teramond

The evolution of QCD coupling constant at finite temperature is considered by making use of the finite temperature renormalization group equation up to the one-loop order in the background field method with the Feynman gauge and the…

High Energy Physics - Theory · Physics 2007-05-23 M. Chaichian , M. Hayashi

An outstanding goal of physics is to find solutions that describe hadrons in the theory of strong interactions, Quantum Chromodynamics (QCD). For this goal, the light-front Hamiltonian formulation of QCD (LFQCD) is a complementary approach…

In the framework of noncompact lattice QED with light fermions, we derive the functional dependence of the average energy per plaquette on the bare parameters using block-spin Renormalization Group arguments and assuming that the…

High Energy Physics - Lattice · Physics 2015-06-25 V. Azcoiti , G. Di Carlo , A. F. Grillo

Quantum Chromodynamics (QCD) is a firmly established part of the Standard Model, yet its long distance properties remain challenging at a conceptual level. In recent years significant experimental and theoretical progress has been made…

High Energy Physics - Phenomenology · Physics 2009-11-07 Paul Hoyer

Analytic versions of QCD are those whose coupling alpha_s(Q^2) does not have the unphysical Landau singularities on the space-like axis (-q^2=Q^2 > 0). The coupling is analytic in the entire complex plane except the time-like axis (Q^2 <…

High Energy Physics - Phenomenology · Physics 2008-12-18 Gorazd Cvetic , Cristian Valenzuela

Quantum chromodynamics in two spacetime dimensions admits a finite non-invertible symmetry described mathematically by a fusion category. This symmetry is spontaneously broken at long distances, leading to distinct vacua. When the theory…

High Energy Physics - Theory · Physics 2024-12-31 Clay Cordova , Diego García-Sepúlveda , Nicholas Holfester

We construct some AdS/QCD models by the systematic procedure of GKN. These models reflect three rather different asymptotics the gauge theory beta functions approach at the infrared region, $\beta\propto-\lambda^2, -\lambda^3$ and…

High Energy Physics - Theory · Physics 2010-05-12 Ding-fang Zeng

The conventional definition of the running coupling $\alpha_{\bar{MS}}(\mu)$ in quantum chromodynamics is based on a solution to the renormalization group equations which treats quarks as either completely massless at a renormalization…

High Energy Physics - Phenomenology · Physics 2009-09-11 Stanley J. Brodsky , Mandeep S. Gill , Michael Melles , Johan Rathsman