Landau-gauge condensates from the quark propagator on the lattice

Abstract

We compute the dimension-2 condensate, <A^2>, and the dimension-4 mixed condensate, <\bar q A q>, from the recent quenched lattice results for the quark propagator in the Landau gauge. We fit the lattice data to the Operator Product Expansion in the "fiducial" region 1.2 GeV < Q < 3 GeV. Our result for the dynamical gluon mass at the scale of 10 GeV^2 is m_A=600-650 MeV, in agreement with independent determinations. For the mixed Landau gauge condensate of dimension-4 we get alpha_s <\bar q g A q> = (-0.11 +/- 0.03) GeV^4. This value is an order of magnitude larger than the <G^2> gluon condensate.