General relations between photoproduction of pions and vector meson production by πN collision based on the photon-vector-meson analogy model

Abstract

The relations among differential cross section, polarization and helicity density matrix elements in γN → πN and πN → VN processes are given for the photon-vector-meson analogy model. For example, the differential cross sections of γN → πN processes are given in terms of density matrix elements and differential cross sections of πN → ϱN processes, and the relations fit the experimental data fairly well.