2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/48704We report on the calculation of the two-loop electroweak, two-photon mediated short-distance dispersive K_L \to μ^+μ^- decay amplitude. QCD corrections change the sign of this contribution and reduce it by an order of magnitude. The resulting amplitude enables us to provide a constraint on the otherwise uncertain long-distance dispersive amplitude.5 pages, 2 figures, presented by K.K. on the conference "Nuclear and Particle Physics with CEBAF", Dubrovnik, Croatia, Nov 3-10, 1998High Energy Physics - Phenomenologytext