  The low-energy limit of pure Yang-Mills SU(3) gauge theory is studied in
Feynman gauge by the method of stationary variance, a genuine second-order
variational method that is suited to deal with the minimal coupling of fermions
in gauge theories. In terms of standard irreducible graphs, the stationary
equations are written as a set of coupled non-linear integral equations for the
gluon and ghost propagators. A physically sensible solution is found for any
strength of the coupling. The gluon propagator is finite in the infrared, with
a dynamical mass that decreases as a power at high energies. At variance with
some recent findings in Feynman gauge, the ghost dressing function does not
vanish in the infrared limit and a decoupling scenario emerges as recently
reported for the Landau gauge.
