NEW CONTRIBUTION TO ANOMALOUS RADIATIVE K(0)-DECAYS

We present a new contribution to the K(L) --> gammagamma amplitude, which is O(p4) within the counting rules of chiral perturbation theory. This direct (non-pole) amplitude, obtained from short-distance s --> dgamma quark diagrams of order eG(F)alpha(s)/pi, and similar s --> dgammagamma diagrams, can account for about half of the experimental amplitude. Closely following the description of the pi0 --> gammagamma and K(L) --> gammagamma processes in the variants of the same low-energy QCD, we find that both of these processes are anomalous in the same sense. Then, by the anomaly-matching principle, we arrive from the chiral-quark to the bosonic counterparts for both of these processes. In this way we add the K(L) --> gammagamma decay to the existing list of anomalous radiative prosesses.