Lattice QCD Green's functions in maximally Abelian gauge: Infrared Abelian dominance and the quark sector

摘要

On lattice gauge field configurations with 2 + 1 dynamical quark flavors, we investigate the momentum space quark and gluon propagators in the combined maximally Abelian plus U(1)(3) x U(1)(8) Landau gauge. We extract the gluon fields from the lattice link variables and study the diagonal and off-diagonal gluon propagators. We find that the infrared region of the transverse diagonal gluon propagator is strongly enhanced compared to the off-diagonal propagator. The Dirac operator from the Asqtad action is inverted on the diagonal and off-diagonal gluon backgrounds separately. In agreement with the hypothesis of infrared Abelian dominance, we find that the off-diagonal gluon background hardly gives rise to any nontrivial quark dynamics while the quark propagator from the diagonal gluon background closely resembles its Landau gauge counterpart.