A Nonperturbative, Schwinger-Dyson-Equation Analysis of Quark Masses and Mixings in a Model with QCD and Higgs Interactions

The Landau gauge Schwinger-Dyson Equation for the quark self-energy is solved in the quenched ladder approximation for several cases of one- and two-quark-generations. The exchanges of Standard Model gluons and Higgs bosons are taken into account. It is found that Higgs boson exchange dominates the quark self-energy for sufficiently large input quark masses (>75 GeV), causing the running quark propagator mass to increase with energy-scale. The running of the quark mixing angles is also considered. No running of the quark mixing angles is found, to one part in a billion, for input quark masses up to and including 500 GeV.