SU(3) Chiral Dynamics with Coupled Channels: Eta and Kaon Photoproduction

We identify the leading s-wave amplitudes of the SU(3) chiral meson-baryon Lagrangian with an effective coupled-channel potential which is iterated in a Lippmann-Schwinger equation. The strangeness S = −1 resonance Λ(1405) and the S11(1535) nucleon resonance emerge as quasi-bound states of anti-kaon/nucleon and kaon/Σ-hyperon. Our approach to meson photoproduction introduces no new parameters. By adjusting a few finite range parameters we are able to simultaneously describe a large amount of low energy data. These include the cross sections of K−p elastic and inelastic scattering, the cross sections of eta meson and kaon photoproduction from nucleons as well as those of pion induced production of etas and kaons (16 different reaction channels altogether). Work supported in part by BMBF and GSI