$ar{K}$ N dynamics at and near threshold energies

Abstract

We have constructed effective separable meson-baryon potentials to match the equivalent chiral amplitudes up to the second order in external meson momenta. The parameters of the model were fitted to the threshold and low energy K−p data including the 1s level characteristics of the kaonic hydrogen atom. We discuss the results of our fits and use the model to calculate the πΣ mass spectrum and the energy dependence of the K−N amplitudes.