PUB - Publikationen an der Universität Bielefeld

We study the lattice artefacts of the Wilson Dirac operator for QCD with twocolors and fermions in the fundamental representation from the viewpoint ofchiral perturbation theory. These effects are studied with the help of thefollowing spectral observables: the level density of the Hermitian Wilson Diracoperator, the distribution of chirality over the real eigenvalues, and thechiral condensate for the quenched as well as for the unquenched theory. Weprovide analytical expressions for all these quantities. Moreover we deriveconstraints for the level density of the real eigenvalues of the non-HermitianWilson Dirac operator and the number of additional real modes. The latter is agood measure for the strength of lattice artefacts. All computations areconfirmed by Monte Carlo simulations of the corresponding random matrix theorywhich agrees with chiral perturbation theory of two color QCD with Wilsonfermions.