Quark-gluon vertex from lattice QCD

Abstract

The quark-gluon vertex in Landau gauge is studied in the quenched approximation using the Sheikholeslami-Wohlert (SW) fermion action with mean-field improvement coefficients in the action and for the quark fields. We see that the form factor that includes the running coupling is substantially enhanced in the infrared, over and above the enhancement arising from the infrared suppression of the quark propagator alone. We define two different momentum subtraction renormalisation schemes -- \MOMT (asymmetric) and \MOMB\ (symmetric) -- and determine the running coupling in both schemes. We find Lambda_msbar(N_f=0)=300(+150/-180)(55)(30) MeV from the asymmetric scheme. This is somewhat higher than other determinations of this quantity, but the uncertainties -- both statistical and systematic -- are large. In the symmetric scheme, statistical noise prevents us from obtaining a meaningful estimate for Lambda_msbar.

33 pages, 12 figures, JHEP3.cls Major restructuring, some discussion of infrared behaviour added, results unchanged. Published version

References in corpus (12)

• On the Infrared Exponent for Gluon and Ghost Propagation in Landau Gauge QCD
• Non-perturbative Landau gauge and infrared critical exponents in QCD
• The Elusiveness of Infrared Critical Exponents in Landau Gauge Yang--Mills Theories
• Gluon propagators and quark confinement
• Instantons and $<A^2>$ Condensate
• Overlap Quark Propagator in Landau Gauge
• Determination of ${\Lambda }_{\overline{MS}}$ from quenched and $N_f=2$ dynamical QCD
• Remarks on the determination of the Landau gauge OPE for the Asymmetric three gluon vertex
• Preliminary Calculation of ${\alpha }_s$ from Green Functions with Dynamical Quarks
• Are Topological Charge Fluctuations in QCD Instanton Dominated?
• Quark-gluon vertex in a momentum subtraction scheme
• Improved non-perturbative renormalization without $c_{NGI}$

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