Non-leptonic kaon decays and the chiral anomaly

An investigation is performed of all non-leptonic kaon decays sensitive to the chiral anomaly. Within the framework of chiral perturbation theory, there are two classes of anomalous amplitudes at O(p4): reducible and direct contributions. Only radiative transitions are affected by the anomaly. The phenomenology of the decays K(L) --> pi+pi-gamma and K+ --> pi+pi0gamma is studied in detail. Including the dominant contributions of O(p6), the experimentally observed dependence of the direct emission amplitude for K(L) --> pi+pi-gamma on the photon energy can be understood. A survey is made of the rare ''anomalous'' decays K --> pipigammagamma and K --> 3pigamma(gamma), including some numerical estimates