Akademik Veri Yönetim Sistemi
14th International Spin Physics Symposium, Osaka, Japonya, 16 - 21 Ekim 2000, cilt.570, ss.551-555
We propose and develop a model for rho (0) and omega photoproduction on nucleons near threshold based on t-, s-, and u-channel amplitudes. In t-channel we consider pi- and sigma- exchanges and we take the coupling constants (g(v), g(t)) in (s+u) nucleon contributions as free parameters. We fit our model to the available experimental differential cross-section data of gamma + p --> p + V reactions. We find that different models which are equivalently good for the description of the differential cross-section on proton targets may be differentiated by their predictions of the beam asymmetry on proton and neutron targets and of the differential cross-section on neutron targets.