- th / 0 10 70 63 v 1 2 5 Ju l 2 00 1 A Theoretical Study of ρ 0 - Photoproduction on Nucleons near Threshold

We investigate the possibility that the process of ρ 0-meson photoproduc-tion on proton, γ + p → p + ρ 0 , in the near threshold region E γ < 2 GeV, can be considered in the framework of model with π-, σ-and N-exchanges. This suggestion is based on a study of the t-dependence of differential cross section, dσ(γp → pρ 0)/dt, which has been measured by SAPHIR Collaboration. We find that the suggested model provides a good description of the experimental data with new values of ρN N-coupling constants in the region of the time-like ρ 0-meson momentum. Our results suggest that such model can be considered as a suitable nonresonant background mechanism for the future discussion of possible role of nucleon resonance contributions. Our predictions for ρ 0-meson photoproduction on neutron target and for beam asymmetry on both proton and neutron targets are presented.