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Related papers: $\alpha_s$ status and perspectives (2018)

200 papers

The strong coupling alpha_s is a fundamental parameter of the Standard Model. In comparison to parameters like alpha_em and M_Z it is relatively poorly known. However the precision of alpha_s measurements has improved dramatically in recent…

High Energy Physics - Phenomenology · Physics 2007-05-23 W. J. Stirling

The four-loop determination of the strong coupling from fully inclusive observables is reviewed. Special attention is given to the low-energy measurement extracted from the hadronic $\tau$ decay width. A recent exhaustive analysis of the…

High Energy Physics - Phenomenology · Physics 2017-04-05 Antonio Pich

We investigate the uncertainty in the value of the strong coupling $\alpha_S(M_Z^2)$ when allowing it to be a free parameter in the recent MMHT global analyses of deep-inelastic and related hard scattering data that was undertaken to…

High Energy Physics - Phenomenology · Physics 2015-10-28 L. A. Harland-Lang , A. D. Martin , P. Motylinski , R. S. Thorne

Recent results on measurements of the strong coupling $\alpha_S$ from LEP are reported. These include analyses of the 4-jet rate using the Durham or Cambridge algorithm, of hadronic $Z^0$ decays with hard final state photon radiation, of…

High Energy Physics - Experiment · Physics 2008-11-26 Stefan Kluth

We present an explicit demonstration that a determination of the strong coupling constant $\alpha_s(m_Z)$ from deep-inelastic scattering and hadron collider data without a simultaneous determination of the parton distribution functions…

High Energy Physics - Phenomenology · Physics 2025-12-01 Stefano Forte , Juan Rojo , Roy Stegeman

We determine the strong coupling alpha_s from a next-to-leading order analysis of processes used for the NNPDF2.1 parton determination, which includes data from neutral and charged current deep-inelastic scattering, Drell-Yan and inclusive…

We present a joint extraction of the strong coupling $\alpha_s$ and the top-quark pole mass $m_t$ from measurements of top-quark pair production performed by the ATLAS and CMS experiments at the 8 TeV LHC. For the first time, differential…

High Energy Physics - Phenomenology · Physics 2020-10-12 Amanda M. Cooper-Sarkar , Michal Czakon , Matthew A. Lim , Alexander Mitov , Andrew S. Papanastasiou

An update of measurements of the strong coupling constant $\alpha_s$ is given, representing the status of September 2002. The results convincingly prove the energy dependence of $\alpha_s$ and are in excellent agreement with the…

High Energy Physics - Experiment · Physics 2011-03-23 Siegfried Bethke

Measurements of $\alpha_s$, the coupling strength of the Strong Interaction between quarks and gluons, are summarised and an updated value of the world average of $\alpha_s (M_Z)$ is derived. Building up on previous reviews, special…

High Energy Physics - Phenomenology · Physics 2009-12-04 Siegfried Bethke

We perform the NLO QCD analysis of the world data on inclusive deep inelastic scattering cross sections of charged leptons off the proton and the deuterium targets. The parton distributions, the value of strong coupling constant…

High Energy Physics - Phenomenology · Physics 2007-05-23 Alekhin Sergey

We present state-of-the-art extractions of the strong coupling based on N$^3$LO+NNLL accurate predictions for the two-jet rate in the Durham clustering algorithm at $e^+e^-$ collisions, as well as a simultaneous fit of the two- and…

The coupling of the strong force, $\alpha_s$, is deemed to be a fundamental parameter of Nature, and, beyond the quark masses, constitutes the only free parameter in the QCD Lagrangian. Provided is an overview of CERN Large Hadron Collider…

High Energy Physics - Experiment · Physics 2015-09-16 Andreas Warburton

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

The measurement of the strong coupling alpha_S using hadronic event shape distributions measured with the OPAL detector at center-of-mass energies between 91 and 209 GeV is summarized. For this measurement hadronic event shape distributions…

High Energy Physics - Experiment · Physics 2011-05-25 Jochen Schieck

Twelve measurements of inclusive cross sections of W$^\pm$ and Z boson production, performed in proton-proton collisions at centre-of-mass energies of 7 and 8 TeV, are compared with perturbative quantum chromodynamics calculations at…

High Energy Physics - Experiment · Physics 2020-06-09 CMS Collaboration

Hadronic final states with a hard isolated photon are studied using data taken at centre-of-mass energies around the mass of the Z0 boson with the OPAL detector at LEP. The strong coupling alpha S is extracted by comparing data and QCD…

High Energy Physics - Experiment · Physics 2009-02-09 The OPAL Collaboration , G. Abbiendi

Data from e+e- annihilation into hadrons collected by the JADE, the L3 and the OPAL experiment at centre-of-mass energies between 14 GeV and 209 GeV are used to determine the strong coupling alpha_S. Observables in leading order sensitive…

High Energy Physics - Experiment · Physics 2017-08-23 J. Schieck

Event Shape Data from $e^+e^-$ annihilation into hadrons collected by the JADE experiment at centre-of-mass energies between 14 GeV and 44 GeV are used to determine the strong coupling $\alpha_S$. QCD predictions complete to…

High Energy Physics - Experiment · Physics 2010-04-15 S. Bethke , S. Kluth , C. Pahl , J. Schieck , the JADE Collaboration

In this contribution we explore one of the many possibilities of determining the strong coupling constant $\alpha_S$ at hadron colliders. The method considered is quite unique compared to other methods in that the value of $\alpha_S$ is…

High Energy Physics - Phenomenology · Physics 2009-10-30 Walter T. Giele

In this proceedings we discuss a prescription to extract the QCD strong coupling constant at $N^{3}LO$ precision in perturbative QCD using a combination of ${\cal{O}}(\alpha_{S}^{3})$ calculations in pQCD and estimations of the…

High Energy Physics - Phenomenology · Physics 2021-10-29 Adam Kardos , Gábor Somogyi , Andrii Verbytskyi