The role of resonances in rare K decays

Abstract

The decays $K \to \pi l^{+} l^{-}$, $K \to \pi \gamma \gamma $ and $K \to \pi \nu {\bar \nu}$ are investigated using the higher order terms of the chiral perturbation theory. The counterterms induced by strong, weak and electromagnetic interactions are determined assuming the resonance exchange. (Talk presented at the Workshop on K-Physics, Orsay, France, 30 May - 4 June, 1996)