Scalar meson dynamics in chiral perturbation theory

A comparison of the linear sigma model [Formula Presented] and chiral perturbation theory (ChPT) predictions for pion and kaon dynamics is presented. Lowest and next-to-leading order terms in the ChPT amplitudes are reproduced if one restricts to scalar resonance exchange. Some low energy constants of the order [Formula Presented] ChPT Lagrangian are fixed in terms of scalar meson masses. Present values of these low energy constants are compatible with the [Formula Presented] dynamics. We conclude that more accurate values would be most useful either to falsify the [Formula Presented] or to show its capability to shed some light on the controversial scalar physics. © 2004 The American Physical Society.