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arXiv · 1004.4135

The low-momentum ghost dressing function and the gluon mass

Abstract

We study the low-momentum ghost propagator Dyson-Schwinger equation (DSE) in Landau gauge, assuming for the truncation a constant ghost-gluon vertex, as it is extensively done, and a simple model for a massive gluon propagator. Then, regular DSE solutions (the zero-momentum ghost dressing function not diverging) appear to emerge and we show the ghost propagator to be described by an asymptotic expression reliable up to the order ${\cal O}(q^2)$. That expression, depending on the gluon mass and the zero-momentum Taylor-scheme effective charge, is proven to fit pretty well the low-momentum ghost propagator obtained through big-volume lattice simulations.

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Ph. Boucaud, M. E. Gómez, J. P. Leroy, A. Le Yaouanc, J. Micheli, O. Pène, J. Rodríguez-Quintero. 2010-04-23. The low-momentum ghost dressing function and the gluon mass. https://doi.org/10.1103/physrevd.82.054007

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