Photoproduction of π 0 Mesons at Helium and at Photon Energies of 160–240 MeV

Abstract

Experimental values of the differential and total cross sections of elastic π0meson photo-production at helium were obtained in the photon-energy interval 160–240 MeV. The measured differential cross sections agree with the calculations based on the already developed theory of the relativistic momentum approximation in the bremsstrahlung energy range E γ ≤ 200 MeV. When corrections for the π0 meson interaction in the final state are introduced, one can obtain agreement with the available experimental data up to energies E γ ≤ 300 MeV. The experimental value of the amplitude ℱ 20 + of π meson photoproduction at nucleons was found for 〈r〉 He = 1.4 F.