Effective chiral theory of kaon nucleon scattering

We apply the relativistic chiral SU(3) Lagrangian density to kaon-nucleon scattering imposing constraints from the pion-nucleon s- and p-wave threshold parameters at chiral order $Q^2$. The s and u channel decouplet baryon exchange is included explicitly and is found to play a crucial role in understanding the empirical s- and p-wave nuclear kaon dynamics quantitatively.