COMPUTATION OF THE RELATION BETWEEN THE BARE LATTICE COUPLING AND THE (MS)OVER-BAR COUPLING IN SU(N) GAUGE-THEORIES TO 2 LOOPS

The perturbation expansion of the ($) over bar M ($) over bar S coupling in the SU(N) gauge theory in powers of the bare lattice coupling is extended to two-loop order. A discussion of our results has already been published elsewhere. We here describe the calculation in some detail. It relies on the background field technique and a recently introduced coordinate space method to evaluate lattice Feynman integrals.