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The Infrared Behaviour of the Running Coupling in Landau Gauge QCD

R. Alkofer·C. S. Fischer·L. von Smekal
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Abstract

Approximate solutions for the gluon and ghost propagators as well as the running coupling in Landau gauge Yang-Mills theories are presented. These propagators obtained from the corresponding Dyson-Schwinger equations are in remarkable agreement with those of recent lattice calculations. The resulting running coupling possesses an infrared fixed point, $α_S(0) = 8.92/N_c$ for all gauge groups SU($N_c$). Above one GeV the running coupling rapidly approaches its perturbative form.

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R. Alkofer, C. S. Fischer, L. von Smekal. 2002-05-13. The Infrared Behaviour of the Running Coupling in Landau Gauge QCD. https://arxiv.org/abs/hep-ph/0205125

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