The Schroedinger functional coupling in quenched QCD at low energies

Abstract

Existing non-perturbative computations of the running coupling of quenched QCD in the Schroedinger functional scheme are extended to scales mu lying much deeper in the low-energy regime. We are able to reach 1/mu ~ 0.9 fm, where a significant deviation from its perturbative evolution is observed.Comment: Lattice2001(improvement), 3 pages, latex2e, 5 Postscript figures, uses epsfig, amssymb and espcrc