Delbrück scattering of 2.754-MeV photons by Pb for angles from 15° to 150°

Abstract
Differential cross sections for the elastic scattering of 2.754-MeV photons by lead have been measured for angles ranging from 15° to 150°. A comparison with theoretical data obtained from the Rayleigh scattering amplitudes of Cornille and Chapdelaine and the Delbrück scattering amplitudes of Papatzacos and Mork shows good agreement at 15°, 120°, and 150° and a discrepancy of up to a factor 1.7 at intermediate angles. Definite evidence for the real part of the Delbrück scattering amplitude has been obtained.