Coherent Scattering of 1.17-Mev and 1.33-Mev Gamma Rays through Small Angles

The dependence of the differential cross section for the coherent scattering of 1.17-Mev and 1.33-Mev gamma rays on atomic number was investigated. An empirical procedure, which makes an absolute determination of the cross sections unnecessary, was used to estimate the Compton scattering cross sections. The latter were subtracted from the measured cross sections in order to obtain the relative coherent scattering cross sections, which were found to vary as $Z^n$. Our average value for $n$ is 3.07±0.18.