Photoproduction of pions on low-energy protons

This paper reports that a study is made of the complete experiment problem and photoproduction of pions on protons. The problem of the volume and content of a complete experiment is solved in the area of photon energies up to 500 MeV for the channels γp-π+n and γp-π → π0p. Experimental data assuring a complete experiment are used for multipole analysis of the channels γp → π+n, π0p and the real and imaginary parts of s- and p-wave multipole amplitudes are obtained. Estimates are produced for the pole parameters (mass and width) of the Δ+33 isobar. An electrical quadrupole amplitude of the transition γp → Δ+33 was found which is significantly different form zero, indicating the existence of a tensor interaction between quarks in hadrons. Data on photoproduction on mesons are used to extract quantitative estimates of the vector and tensor constants of interaction of an ω meson with nucleons