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Abstract: We discuss kinematical enhancements of cutoff effects at short and intermediate distances. Starting from a pedagogical example with periodic boundary conditions, we switch to the case of the Schrödinger functional, where the theoretical analysis is checked by precise numerical data with dynamical -improved Wilson quarks. Finally we present an improved determination of the renormalization of the axial current in that theory. [Copyright &y& Elsevier]

Abstract: We simulate two-dimensional QED with two degenerate Wilson fermions and plaquette gauge action. As a consequence of the Mermin–Wagner theorem, in the continuum limit chiral symmetry is realized à la Wigner. This property affects also the size of the cutoff effects. That can be understood in view of the fact that the leading lattice artifacts are described, in the continuum Symanzik effective theory, by chirality breaking terms. In particular, vacuum expectation values of non-chirality-breaking operators are expected to be improved in the chiral limit. We provide a numerical confirmation of this expectation by performing a scaling test. [Copyright &y& Elsevier]

Abstract: The running of renormalized quark masses is computed in lattice QCD with two flavors of massless improved Wilson quarks. The regularization and flavor independent factor that relates running quark masses to the renormalization group invariant ones is evaluated in the Schrödinger functional scheme. Using existing data for the scale and the pseudoscalar meson masses, we define a reference quark mass in QCD with two degenerate quark flavors. We then compute the renormalization group invariant reference quark mass at three different lattice spacings. Our estimate for the continuum value is converted to the strange quark mass with the help of chiral perturbation theory. [Copyright &y& Elsevier]

Abstract: We report our final estimate of the b-quark mass from lattice QCD simulations using Heavy Quark Effective Theory non-perturbatively matched to QCD at . Treating systematic and statistical errors in a conservative manner, we obtain after an extrapolation to the physical point. [Copyright &y& Elsevier]