Circular Wilson loop in N = 2^* super Yang-Mills theory at two loops and localization

We present a two-loop calculation of the supersymmetric circular Wilson loop in the N = 2^* super Yang-Mills theory on the four-sphere. We develop an efficient framework for computing contributing Feynman graphs that relies on using the embedding coordinates combined with the Mellin-Barnes techniques for propagator-like integrals on the sphere. Our results exactly match predictions of supersymmetric localization providing a nontrivial consistency check for the latter in non-conformal settings.