ππ and πKscattering in unitarized chiral perturbation theory

Abstract

The inverse-amplitude method has previously been applied to ${\mathit{K}}_{\mathit{l}4}$ decays in order to determine some of the phenomenological low-energy constants. These phenomenological constants occur also in the inverse-amplitude method applied to \ensuremath{\pi}\ensuremath{\pi} and \ensuremath{\pi}K scattering. In order to investigate whether this method can systematically extend the range of applicability of chiral perturbation theory, finite predictions are obtained for these scattering processes. It is found that the inverse-amplitude method improves the behavior of chiral perturbation theory, suggesting that the inverse-amplitude method is a rather systematical approach.