Kaon-pion low energy phase shifts from chiral perturbation theory

In this work, we fix three chiral perturbation theory (ChPT) parameters by fitting low energy S- and P-wave kaon-pion phase shifts with the ChPT scattering amplitude. We get the K∗ resonance, positive and large isospin one-half S-wave and a negative and small 32 S-wave phase shifts, compatible with experimental data. We compare our method with other approaches, in particular with the unitarization program of current algebra.