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Semiperturbative construction for the quark-gluon vertex

Felipe J. Llanes-Estrada·Christian S. Fischer·Reinhard Alkofer
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Abstract

We construct a model for the quark-gluon vertex of Landau gauge QCD. This is of twofold interest: on the one hand the quark-gluon interaction is at the heart of quark confinement, on the other hand it is a central element in hadron phenomenology based on QCD Greens functions. We employ the non-Abelian one-loop diagram in perturbation theory, which is of order Nc. As a novelty we replace the tree-level quark and gluon propagators in this diagram by their dressed counterparts solving the Dyson-Schwinger equations. The Nc-suppressed Abelian diagram is an order of magnitude smaller in various kinematics. We also study the effect of ghost dressing factors on the vertex obtaining a construction in good agreement with recent low-momentum lattice calculations.

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Felipe J. Llanes-Estrada, Christian S. Fischer, Reinhard Alkofer. 2004-07-29. Semiperturbative construction for the quark-gluon vertex. https://arxiv.org/abs/hep-ph/0407332

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