Proton Compton Effect

Abstract

A method of calculating cross-sections of Compton scattering on protons based on dispersion relations at a fixed square of the momentum transferred with a subtraction for invariant amplitudes is thoroughly discussed in this review. Dispersion sum rules for the interaction constants of πo, η and Xo mesons are analysed. A comparison is made by means of x2-test. The results obtained from the comparison of the experimental data in the range of energies up to 300 MeV with the theoretical cross-sections are presented. In the range of gamma-ray energies from 180 to 220 MeV a strong difference between theoretical calculations and experimental data is observed. In the other ranges of energy the experimental data available are in agreement with the theoretical calculations, the contribution from the annihilation channel being considered and the sign of the contribution from the π°-meson pole being chosen equal to the sing of the main amplitude.