Infrared finite ghost propagator in the Feynman gauge
Abstract
We demonstrate how to obtain from the Schwinger-Dyson equations of QCD an infrared finite ghost propagator in the Feynman gauge. The key ingredient in this construction is the longitudinal form factor of the non-perturbative gluon-ghost vertex, which, contrary to what happens in the Landau gauge, contributes non-trivially to the gap equation of the ghost. The detailed study of the corresponding vertex equation reveals that in the presence of a dynamical infrared cutoff this form factor remains finite in the limit of vanishing ghost momentum. This, in turn, allows the ghost self-energy to reach a finite value in the infrared, without having to assume any additional properties for the gluon-ghost vertex, such as the presence of massless poles. The implications of this result and possible future directions are briefly outlined.
Cite
@article{arxiv.0712.0780,
title = {Infrared finite ghost propagator in the Feynman gauge},
author = {A. C. Aguilar and J. Papavassiliou},
journal= {arXiv preprint arXiv:0712.0780},
year = {2008}
}
Comments
22 pages, 9 figures