Low-energy meson processes and parameters of the effective chiral p/sup 4/ Lagrangian

The role of the p/sup 4/ corrections in the description of meson processes is discussed from the point of view of an experimental test of the low-energy chiral QCD theory. It is shown that the effective p/sup 4/ Lagrangian which occurs in this theory describes satisfactorily the ..pi pi.. and ..pi..K scattering lengths and the parameters of the expansion of the K..-->..3..pi.. decay amplitudes in powers of the invariant Dalitz variables. Experimental data on these processes with much greater accuracy will be required for a more detailed analysis of the p/sup 4/ corrections.