Научно-исследовательский институт ядерной физики имени Д.В. Скобельцына
Московского государственного университета имени М.В. Ломоносова

We solve Dyson-Schwinger equations for pure gluodynamics at two loops for
quark and gluon propagators.
A gauge-invariant bilocal condensate is constructed, which is fully
determined by the solutions of Dyson---Schwinger equations. This allows us
to obtain the condensate dependence on point separation, consistent with
OPE
for small distances and lattice results for large distances. Correllation
length of the bilocal condensate in the IR and UV are estimated. We
conclude
that this method yields qualitatively reliable predictions for condensates,
and introduction of quarks could make a useful phenomenological tool of it.