φ photoproduction near threshold with Okubo-Zweig-Iizuka evading φNN interactions

Existing intermediate and high energy φ-photoproduction data is consistent with purely diffractive production (i.e., Pomeron exchange). However, near threshold (1.574 GeV<E_γˡᵃᵇ<~2.0 GeV) the energy dependence of the diffractive amplitude is not well known and nondiffractive amplitudes such as π⁰ and η exchange, ss̄ knockout, and nonzero φNN couplings can give sizable contributions to the cross section and polarization density matrix elements of the →φK⁺K^- decay angular distribution. We stress the importance of measurements with linearly polarized photons near the φ threshold to separate natural and unnatural parity exchange mechanisms. Approved and planned φ photoproduction and electroproduction experiments at Jefferson Lab will help establish the relative dynamical contributions near threshold and clarify outstanding theoretical issues related to apparent Okubo-Zweig-Iizuka violations.