2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/45535Because of the infrared renormalons, it is difficult to get power accuracy in the traditional approach to the Wilson's operator product expansion. Based on a new perturbative renormalization scheme for power-divergent operators, I propose a practical version of the OPE that allows to calculate power corrections to desired accuracy. The method is applied to the expansion of the vector-current correlation function in QCD vacuum, in which field theoretical status of the gluon condensate is discussed.8 pages in REVTEXHigh Energy Physics - PhenomenologyHigh Energy Physics - LatticeHigh Energy Physics - Theorytext