S-wave phase shifts and non-perturbative chiral approach
Physik Department T39, Technische Universität München, D-85747 Garching, Germany
Received: 17 August 1998 / Revised version: 21 September 1998 Communicated by F. Lenz
We extend a recent non-perturbative chiral approach to S-wave scattering of Oller and Oset by including the couplings to the -channel. We find that the isospin-zero and isospin-two S-wave phase shifts of the model deviate considerably from a recent solution of the Roy-equations. Including the couplings with the -channel does not improve the situation. In particular, no -meson like enhancement structure shows up in the Roy-equation solution. We also consider the -scattering lengths in this approach.
12.39.Fe Chiral lagrangians - 13.75.Lb Meson-meson interactions