Non-perturbative Power Corrections to Ghost and Gluon Propagators

TL;DR

This paper investigates the main non-perturbative power corrections to ghost and gluon propagators in Landau gauge Yang-Mills theory, demonstrating their impact and the consistency of the theoretical approach using OPE and lattice data.

Contribution

It provides a detailed analysis of non-perturbative power corrections in ghost and gluon propagators, showing the equality of Wilson coefficients and the significance of these corrections.

Findings

The ratio of ghost to gluon propagators is free from dominant power corrections.

Perturbative fits yield different $\\Lambda_{\ms}$ values when using propagators separately versus their ratio.

Significant non-perturbative $\sim 1/q^2$ power corrections are present in the propagators.

Abstract

We study the dominant non-perturbative power corrections to the ghost and gluon propagators in Landau gauge pure Yang-Mills theory using OPE and lattice simulations. The leading order Wilson coefficients are proven to be the same for both propagators. The ratio of the ghost and gluon propagators is thus free from this dominant power correction. Indeed, a purely perturbative fit of this ratio gives smaller value ($\simeq 270$MeV) of $\Lambda_{\ms}$ than the one obtained from the propagators separately($\simeq 320$MeV). This argues in favour of significant non-perturbative $\sim 1/q^2$ power corrections in the ghost and gluon propagators. We check the self-consistency of the method.