Determination of the QCD Coupling ${\alpha }_s$

Abstract

Theoretical basics and experimental determinations of the coupling parameter of the Strong Interaction, ${\alpha }_s$, are reviewed. The world average value of ${\alpha }_s$, expressed at the energy scale of the rest mass of the $Z^0$ boson, is determined from analyses which are based on complete NNLO perturbative QCD. The result is ${\alpha }_s(M_Z)=0.1184\pm 0.0031$. No significant deviations or systematic biases of subsamples of experimental results are found. From the observed energy dependence of ${\alpha }_s$, which is in excellent agreement with the expectations of QCD, the number of colour degrees of freedom can be constrained to $N_c=3.03\pm 0.12$.

49 pages, 12 figures, to be published in Journal of Physics G

References in corpus (1)

• Resummation of thrust distributions in DIS

Cited by in corpus (103)

• Precision Electroweak Measurements on the Z Resonance
• The Muon g-2
• Jet Substructure at the Large Hadron Collider: A Review of Recent Advances in Theory and Machine Learning
• The 2009 World Average of ${\alpha }_s$
• The 3-, 4-, and 5-flavor NNLO Parton from Deep-Inelastic-Scattering Data and at Hadron Colliders
• The Physics of Hadronic Tau Decays
• Master Formulae for Delta F=2 NLO-QCD Factors in the Standard Model and Beyond
• 50 Years of Quantum Chromodynamics
• Exclusive processes in position space and the pion distribution amplitude
• Two-Loop QCD Helicity Amplitudes for $e^{+}{e}^{-}\to 3$~Jets
• The Two-Loop QCD Matrix Element for $e^{+}{e}^{-}\to 3$ Jets
• Mellin Moments of the {$O({\alpha }_s^3$)} Heavy Flavor Contributions to unpolarized Deep-Inelastic Scattering at $Q^2\gg m^2$ and Anomalous Dimensions
• The hadronic contributions to the anomalous magnetic moment of the muon
• Non--Singlet QCD Analysis of Deep Inelastic World Data at \boldmath $O({\alpha }_s^3)$
• Jet quenching and medium response in high-energy heavy-ion collisions: a review
• Experimental Tests of Asymptotic Freedom
• An NLO QCD analysis of inclusive cross-section and jet-production data from the ZEUS experiment
• Sudakov resummation of multiparton QCD cross sections
• Hadronic light-by-light scattering in the muon g-2: a new short-distance constraint on pion exchange
• A study of the energy evolution of event shape distributions and their means with the DELPHI detector at LEP
• Precision Determination of the Pion Form Factor and Calculation of the Muon $g-2$
• Inclusive jet cross sections in the Breit frame in neutral current deep inelastic scattering at HERA and determination of alpha_s
• Low-Energy Supersymmetry and the Tevatron Bottom-Quark Cross Section
• Monte Carlo simulation for jet fragmentation in SUSY-QCD
• Testing perturbation theory on the nf=0 static quark potential
• Tests of Quantum Chromo Dynamics at e^+e^- Colliders
• The Threshold t-tbar Cross Section at NNLL Order
• Quark-gluon vertex from lattice QCD
• Real radiation at NNLO: e^+e^- to 2 jets through O(alpha_s^2)
• Inclusive-jet and dijet cross sections in deep inelastic scattering at HERA
• Calculation of Non-Leptonic Kaon Decay Amplitudes from $K\to \pi$ Matrix Elements in Quenched Domain-Wall QCD
• ${\alpha }_s$ at Zinnowitz 2004
• Inclusive-jet photoproduction at HERA and determination of alphas
• Improved Calculation of F2 in Electroproduction and xF3 in Neutrino Scattering to NNLO and Determination of alpha_s
• Bilocal expansion of the Borel amplitude and the hadronic tau decay width
• Higher Twist Contributions to the Structure Functions F_2^p(x,Q^2) and F_2^d(x,Q^2) at Large x and Higher Orders
• The Cross Section of e^+ e^- Annihilation into Hadrons of Order alpha_s^4 n_f^2 in Perturbative QCD
• Generalized resummation of QCD final-state observables
• Scaling Rule for Nonperturbative Radiation in a Class of Event Shapes
• Scaling of Power Corrections for Angularities from Dressed Gluon Exponentiation
• Jet-radius dependence of inclusive-jet cross sections in deep inelastic scattering at HERA
• Inclusive-jet cross sections in NC DIS at HERA and a comparison of the kT, anti-kT and SIScone jet algorithms
• Measurement of dijet production in neutral current deep inelastic scattering at high Q**2 and determination of alpha_s
• Nonsinglet parton distribution functions from the precise next-to-next-to-next-to leading order QCD fit
• Double diffractive rho-production in gamma^* gamma^* collisions
• Non-Singlet QCD Analysis of the Structure Function F_2 in 3-Loops
• Substructure dependence of jet cross sections at HERA and determination of alphas
• D and D_{S} decay constants from QCD duality at three loops
• NNLO QCD contributions to the flavor non-singlet sector of ${\mathbf{F}}_2(\mathbf{x},{\mathbf{Q}}^2)$
• Forward jet production in deep inelastic ep scattering and low-x parton dynamics at HERA
• ${\alpha }_s$ 2002
• Three-Jet Production in Deep-Inelastic Scattering at HERA
• Scaling violations and determination of alpha_s from jet production in gamma-p interactions at HERA
• Multijet production in neutral current deep inelastic scattering at HERA and determination of alpha_s
• Diffractive production of two rho^0_L mesons in e^+e^- collisions
• A novel series solution to the renormalization group equation in QCD
• Resummation of the hadronic tau decay width with the modified Borel transform method
• QCD Effective Coupling in the Infrared Region
• QCD Studies at LEP
• Resummed jet rates for $e^{+}{e}^{-}$ annihilation into massive quarks
• Determination of alpha_s from scaling violations of truncated moments of structure functions
• Scale- and scheme-independent extension of Pade approximants; Bjorken polarized sum rule as an example
• An Invariant Charge Model for All q^2>0 in QCD and Gluon Condensate
• All-orders infra-red freezing of R(e+e-) in perturbative QCD
• Precision measurements of alphas at HERA
• Analytic Perturbation Theory for Practitioners and Upsilon Decay
• Modified Fragmentation Function from Quark Recombination
• Upsilon Decay to a Pair of Bottom Squarks
• Calculation of ${\bar{\alpha }}_{Q.E.D.}$ on the Z
• Analytical QCD and multiparticle production
• Value of alpha_s from deep-inelastic-scattering data
• Evolution of Parton Fragmentation Functions at Finite Temperature
• B and B_s decay constants from QCD Duality at three loops
• Nonlinearity of Regge trajectories in the scattering region
• Direct Extraction of QCD Lambda MS-bar from e+e- Jet Observables
• The NNLO non-singlet QCD analysis of parton distributions based on Bernstein polynomials
• Light Gluino and the Running of alpha_s
• Extraction of alpha_s from the Gross--Llewellyn Smith sum rule using Borel resummation
• Applied High Energy QCD
• Cancellation of Sudakov Logarithms in Radiative Decays of Quarkonia
• Elastic ${\pi }^{+}p$ and ${\pi }^{+}{\pi }^{+}$ scattering at LHC
• Subjet distributions in deep inelastic scattering at HERA
• Determination of the high-twist contribution to the structure function $x{F}_3^{\nu N}$
• New extraction of alpha_s(MZ) from proton DIS data
• Measurement of the longitudinal and transverse cross-section in e^+e^- annihilation at sqrt(s)=35-44 GeV
• B and B_S decay constants from moments of Finite Energy Sum Rules in QCD
• Analytic Perturbation Theory for QCD observables
• Measurements of ${\alpha }_s$ from event shapes and the four-jet rate
• Jet physics in e+e- annihilation from 14 to 209 GeV
• The Puzzle of the Bottom Quark Production Cross Section
• Angular correlations in three-jet events in ep collisions at HERA
• Theoretical uncertainties for measurements of alpha_s from electroweak observables
• Nonlinearity of vacuum reggeons and exclusive diffractive production of vector mesons at HERA
• In search of the QCD-Gravity correspondence
• Highlights of Short Baseline Physics at a Neutrino Factory
• Tests of Three-Flavor Chiral Perturbation Theory
• Fundamental Parameters from Precision Tests
• Summary of Working Group 3 of the Neutrino Factory '02 Workshop
• Fragmentation functions using e+e- data from PETRA and LEP
• Basic Parameters and Some Precision Tests of the Standard Model
• Tests of hard and soft QCD with e+e- Annihilation Data
• Holography in Quark-Gluon Plasma and Neutron Stars
• QCD at high energy (experiments)