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Related papers: The QCD Running Coupling and its Measurement

200 papers

A vast program of determinations of the strong coupling $\alpha_\mathrm{S}$ is being undertaken by CMS. These measurements exploit several QCD-dominated processes that are sensitive to $\alpha_\mathrm{S}$, and present different theoretical…

High Energy Physics - Experiment · Physics 2024-09-25 Patrick L. S. Connor

A recent lattice calculation of the QCD running coupling is presented. The coupling is extracted from the force between two static quarks in the framework of the valence quark approximation. A value of the Lambda-parameter for zero quark…

High Energy Physics - Lattice · Physics 2009-09-25 Gunnar S. Bali

We consider a definition of the QCD running coupling constant $\alpha(\mu)$ related to Wilson loops of size $r{\times}t$ with arbitrary fixed $t/r$. The schemes defined by these couplings are very close to the $\overline{\rm MS}$ scheme for…

High Energy Physics - Lattice · Physics 2009-10-28 Massimo Campostrini , Paolo Rossi , Ettore Vicari

Recent results in light hadron spectroscopy are reviewed. Attention is given to the requirements of precision determinations in lattice gauge theory. Different methods for extracting the running coupling constant $\alpha_S$ are compared.…

High Energy Physics - Lattice · Physics 2008-11-26 Chris Michael

A simple parametrization of the QCD running coupling at low scales is introduced and used to illustrate various schemes for the estimation of non-perturbative power corrections. The `infrared matching' scheme proposed earlier gives…

High Energy Physics - Phenomenology · Physics 2010-02-03 B. R. Webber

This document collects a written summary of all contributions presented at the workshop "$\alpha_s$(2019): Precision measurements of the strong coupling" held at ECT* (Trento) in Feb. 11--15, 2019. The workshop explored in depth the latest…

The frozen QCD coupling is a parameter often used as an effective fixed coupling. It is supposed to mimic both the running coupling effects and the lack of knowledge of alpha_s in the infrared region. Usually the value of the frozen…

High Energy Physics - Phenomenology · Physics 2013-02-21 B. I. Ermolaev , M. Greco , S. I. Troyan

The current status of the QCD coupling constant $\alpha_S$ and experimental and theoretical studies of hadronic jets are reviewed.

High Energy Physics - Phenomenology · Physics 2007-05-23 B R Webber

We consider a definition of the QCD running coupling constant $\alpha(\mu)$ related to Wilson loops of size $r{\times}t$ with arbitrary fixed $t/r$. The schemes defined by these couplings are very close to the $\overline{\rm MS}$ scheme…

High Energy Physics - Lattice · Physics 2009-10-28 Massimo Campostrini , Paolo Rossi , Ettore Vicari

The QCD analytic running coupling alpha_{an} which has no nonphysical singularities for all Q^2>0 is considered for the initial perturbation theory approximations up to four loop order. The finiteness of the analytic coupling at zero is…

High Energy Physics - Phenomenology · Physics 2009-11-07 Aleksey I. Alekseev

We present two determinations of the strong coupling \(\alpha_s\). The first one is from the static energy at three-loop accuracy, and may be considered an update of earlier determinations by some of us. The new analysis includes new…

The study of QCD processes at the LHC will serve two main goals. First, the predictions of Quantum Chromodynamics will be tested and precision measurements will be performed, allowing additional constraints to be established, and providing…

High Energy Physics - Phenomenology · Physics 2019-08-14 Vasiliki A. Mitsou

By (a) using an expression for the LATTICE potential of QCD in terms of a CONTINUUM running coupling and (b) globally parameterizing this coupling to interpolate between 2- (or higher-) loop QCD in the UV and the flux tube prediction in the…

High Energy Physics - Lattice · Physics 2009-10-28 Timothy R. Klassen

We propose a new method to compute the running coupling constant of gauge theories on the lattice. We first give the definition of the running coupling in the new scheme using the Wilson loops in a finite volume, and explain how the running…

We present a non-perturbative computation of the running of the coupling alpha_s in QCD with two flavours of dynamical fermions in the Schroedinger functional scheme. We improve our previous results by a reliable continuum extrapolation.…

High Energy Physics - Lattice · Physics 2010-04-05 Michele Della Morte , Roberto Frezzotti , Jochen Heitger , Juri Rolf , Rainer Sommer , Ulli Wolff

The brief overview of the definite determinations of the QCD coupling constant $\alpha_s$ from the characteristics of deep-inelastic scattering processes is given.

High Energy Physics - Phenomenology · Physics 2008-02-03 Andrei L. Kataev

In line with some previous works, we study in this paper the meson spectrum in the framework of a second order quark-antiquark Bethe-Salpeter formalism which includes confinement. An analytic one loop running coupling constant alpha_s(Q),…

High Energy Physics - Phenomenology · Physics 2009-11-10 M. Baldicchi , G. M. Prosperi

We present a new determination of the strong coupling constant from lattice QCD simulations. We use four different short-distance quantities to obtain the coupling, three different (infrared) meson splittings to tune the simulation…

High Energy Physics - Lattice · Physics 2016-08-24 C. T. H. Davies , K. Hornbostel , G. P. Lepage , P. McCallum , J. Shigemitsu , J. Sloan

We investigate the occurrence of power terms $(Lambda^2/p^2$ in the running QCD coupling by analysing non-perturbative measurements of $\alpha_s(p)$ at quite low momenta obtained from the lattice three-gluon vertex. Our study provides some…

High Energy Physics - Lattice · Physics 2009-10-31 G. Burgio , F. Di Renzo , C. Parrinello , C. Pittori

We report on the non-perturbative computation of the running coupling of two-flavour QCD in the Schr"odinger functional scheme. The corresponding Lambda-parameter, which describes the coupling strength at high energy, is related to a low…