Two-point function of strangeness-carrying vector currents in two-loop chiral perturbation theory - art. no. 114025

We calculate the correlator between two external vector currents having the quantum numbers of a charged kaon. We give the renormalized expression to two loops in standard chiral perturbation theory in the isospin limit, whic h, as a physical result, is finite and scale independent. Applications incl ude a lour energy theorem, valid at two loop order, of a flavor breaking co mbination of vector current correlators, as well as a determination of the phenomenologically relevant finite O(p(6))-counterterm combination Q(V) by means of inverse moment finite energy sum rules. This determination is less sensitive to isospin-breaking effects than previous attempts.