Nonelastic Scattering of Fast Neutrons

The relative angular distributions of neutrons inelastically scattered from iron, yttrium, zirconium, radiogenic lead (88% ${\mathrm{Pb}}^{206}$), lead, and bismuth were measured for neutrons in the region from 3.7 to 4.7 Mev. The relative angular distributions of the low energy (0.5 to 4 Mev) neutrons resulting from nonelastic scattering of 15.2-Mev neutrons were also measured. In each case the distributions were found to be isotropic within experimental error (±15%), therefore supporting earlier evidence of compound nucleus formation as the predominant interaction mechanism.