Regge phenomenology of pion photoproduction off the nucleon at forward   angles
  We present a Regge model for pion photoproduction which is basically free of parameters within the framework of the s-channel helicity amplitude. We use coupling constants of all exchanged mesons determined from empirical decay widths or from the SU(3) relations together with consistency check with existing estimates that are widely accepted in other reaction processes. Cross sections and spin polarization asymmetries at various photon energies are analyzed and results are obtained in better agreement with experimental data without referring to any fitting procedure. 
Byung Geel Yu, Tae Keun Choi, W. Kim
nucl-th hep-ph nucl-ex