Neutron-proton scattering with 90-Mev neutrons has been investigated by others, using a proportional counter technique and also using a cloud chamber, and the scattering cross section for neutrons for center-of-mass angles from 36° to 180° has been measured. The present experiment was an attempt to overlap the data of Hadley, et al., from 74° to 36° and to extend the cross-section measurements to smaller angles. This experiment was performed with nuclear emulsions in order to permit the detection of protons down to about 1.5 Mev, and to avoid systematic errors which might be present in the case of other methods of detection. The results agree with those of Hadley, et al., within the probable error, and the cross-section curve exhibits beyond 36° the same general trend as does their curve.

• Received 13 October 1950

DOI:https://doi.org/10.1103/PhysRev.81.493