The Role of Low Mass Nucleon Resonances in Near Threshold ω Meson Photoproduction

We investigate the role of the nucleon resonances with masses M_N* ≤ 1720 MeV in ω meson photoproduction at low energy with E_γ < 1.25 GeV. The amplitude is calculated within effective Lagrangian approach, which includes, at the tree level, leading t-channel pseudoscalar meson exchange, nucleon Born terms and nucleon resonance excitations. For the later part we use an effective Lagrangians motivated by previous studies of π and η photoproduction. The contributions from the nucleon resonances are found to be significant relative to the all other channels in changing the differential cross sections in a wide interval of t In particular, we suggest that a crucial test of our predictions can be made by measuring single and double spin asymmetries.