VECTOR-MESON DOMINANCE AND HIGH-ENERGY ELECTROPRODUCTION OF RHO MESON

The vector-meson dominance (VMD) model is applied to the high-energy electroproduction of ρ mesons off unpolarized protons. It is shown that an experimental study of the angular distribution of the two pions produced from the decay of the final ρ can be used to measure directly the total ρp cross sections for transversely and longitudinally polarized ρ mesons. The ratio of these cross sections is important in the VMD theory of ep inelastic scattering. An expression for the differential cross section of the electroproduction of ρ mesons in the forward direction of the ρp scattering is also given in terms of these two cross sections. The q2 dependence of the ρ-electroproduction amplitude is predicted, and certain checks of the model are also given. © 1969 The American Physical Society.