The differential elastic scattering cross section of 9.0 MeV photons by 181Ta has been measured at angles between 25° and 140° and a good agreement was obtained between the measured and predicted values at θ = 35-90°. In calculating the theoretical cross sections the coherent scattering contributions of nuclear Thomson (NT), nuclear resonance (NR) and Delbrück (D) amplitudes were included while that of Rayleigh (R) scattering was excluded. The D-amplitudes were taken from a recent calculation by Mork and Papatzacos. Evidence for the contribution of the real D-amplitude is obtained.
- Nuclear reaction