High loop renormalization constants for Wilson fermions/Symanzik improved gauge action

Abstract

We present the current status of our computation of quark bilinear renormalization constants for Wilson fermions and Symanzik improved gauge action. Computations are performed in Numerical Stochastic Perturbation Theory. Volumes range from 10^4 to 32^4. Renormalization conditions are those of the RI'-MOM scheme, imposed at different values of the physical scale. Having measurements available at several momenta, irrelevant effects are taken into account by means of hypercubic symmetric Taylor expansions. Finite volumes effects are assessed repeating the computations at different lattice sizes. In this way we can extrapolate our results to the continuum limit, in infinite volume.Comment: 8 pages, 3 figures, talk presented at the 27th International Symposium on Lattice Field Theory (Lattice 2009), Beijing, China, 26-31 Jul 200