ETA PHOTOPRODUCTION IN A COUPLED-CHANNELS APPROACH [chapter]

A. WALUYO, C. BENNHOLD, G. PENNER, U. MOSEL
2001 NSTAR 2001  
Eta photoproduction on the nucleon is studied in a coupled-channels approach based on an effective Lagrangian. We compare to new differential cross section and beam asymmetry data data from the GRAAL collaboration. At energies above the S 11´1 535µ region we find no sign of p-wave nucleon resonance contributions. The forward-peaking of the beam asymmetry data at higher energy is explained in terms of vector meson t-channel contributions. These new polarization data also reveal a novel role
more » ... l a novel role played by the D 13´1 700µ state, similar to the role of the D 13´1 520µ at lower energy.
doi:10.1142/9789812810878_0030 fatcat:2leuu3cov5fn5o72wlh7spaoz4