Three-point vertex functions in Yang-Mills Theory and QCD in Landau gauge

¹ Institute of Physics, University of Graz, NAWI Graz, Universitätsplatz 5, 8010 Graz, Austria
² Department of Physics, Washington University, St. Louis, MO, 63130, USA

^a e-mail: adrian.blum@uni-graz.at
^b e-mail: reinhard.alkofer@uni-graz.at
^c e-mail: markus.huber@uni-graz.at
^d e-mail: windisch@physics.wustl.edu

Published online: 22 March 2017

Abstract

Solutions for the three-gluon and quark-gluon vertices from Dyson-Schwinger equations and the three-particle irreducible formalism are discussed. Dynamical quarks (“unquenching”) change the three-gluon vertex via the quark-triangle diagrams which themselves include fully dressed quark-gluon vertex functions. On the other hand, the quark-swordfish diagram is, at least with the model used for the two-quark-two-gluon vertex employed here, of minor importance. For the leading tensor structure of the threegluon vertex the “unquenching” effect can be summarized for the nonperturbative part as a shift of the related dressing function towards the infrared.