Abstract
We apply the effective Lagrangian approach to investigate the role of the nucleon resonances in -meson photoproduction at energies near the threshold. The nonresonant amplitudes are taken from the previous investigations at higher energies and consist of the pseudoscalar meson exchange and the nucleon Born terms. The resonant amplitudes are calculated from effective Lagrangians with the and coupling constants fixed by the empirical helicity amplitudes and the vector meson dominance model. The contributions from the nucleon resonances are found to be significant in changing the differential cross sections in a wide interval of t and various spin observables. In particular, we suggest that a crucial test of our predictions can be made by measuring single and double spin asymmetries.
- Received 6 March 2002
DOI:https://doi.org/10.1103/PhysRevC.66.015204
©2002 American Physical Society