Renormalization of the iso-singlet scalar density in lattice QCD with Wilson quarks

Abstract

Due to the absence of an exact chiral symmetry in lattice QCD with Wilson fermions, the iso-singlet scalar density has to be renormalized both additively and multiplicatively. We propose to use chiral Ward identities between correlation functions derived from the Schrödinger functional to determine the relevant renormalization constants directly in the chiral limit. Although the method does not rely on perturbation theory, we here use it to determine the renormalization constants and to obtain an idea of the typical size of cutoff effects. Finally we comment on the prospects for a direct determination of the chiral condensate as expectation value of a renormalized scalar density.