Application of a modified K-matrix formalism to ππ and [formula omitted] scattering

Abstract

With the help of the recently proposed modified K-matrix foralism [1] wee perform a coupled-channel calculation for ππ and K K . Crossed-channel influences are taken into account for ππ → ππ by iteration and for ππ → K K and ZK K → K K on a phenomenological basis. Direct-channel resonances are treated as coupled single-particle states. In the ππ channel we find good agreement with experiments below 1.2 GeV although we disagree with the results from linear current algebra models. The K K 's wave phase shift above threshold agrees with the down solution of experiments. Our predictions for the s-wave amplitudes ππ → K K below K K threshold are somewhat different to other authors; the higher partial waves are qualitatively similar to the prediction of other authors.