Non-perturbative power corrections to ghost and gluon propagators

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 (similar or equal to 270MeV) of Delta((MS)) over bar than the one obtained from the propagators separately(similar or equal to 320MeV). This argues in favour of significant non-perturbative similar to 1/q(2) power corrections in the ghost and gluon propagators. We check the self-consistency of the method.