Probing proton strangeness with time-like virtual Compton scattering

Abstract

We document that p(γ,e+e−)p measurements will yield new, important information about the off-shell time-like nucleon form factors, especially in the φ meson region (q2=M2φ) governing the φN couplings gV,TφNN. Calculations for p(γ,e+e−)p, utilizing vector meson dominance, predict measurable φ enhancements at high |t| compared to the expected φ background production from π, η and Pomeron exchange. The φ form factor contribution generates a novel experimental signature for OZI violation and the proton strangeness content. The φN couplings are determined independently from a combined analysis of the neutron electric form factor and recent high |t| φ photoproduction. The π, η and Pomeron transition form factors are also predicted and the observed π and η transition moments are reproduced.