On the Scattering of Fast Neutrons by Protons and Deuterons

The scattering cross sections of the proton, deuteron, and the carbon nucleus have been determined for 4.1-, 12.5-, and 13.5-Mev neutrons by detecting the corresponding recoil protons. A coincidence set of three proportional counters was used. Similar measurements were made with 14-Mev neutrons from the reactions D+Li. These were detected by the 9.9-min. activity arising from the reaction ${}_{29}{}^{}{}_{}{}^{}\mathrm{Cu}_{}^{63}{}_{}{}^{}+{}_0{}^{}{}_{}{}^{}n_{}^1{}_{}{}^{}\to {}_{29}{}^{}{}_{}{}^{}\mathrm{Cu}_{}^{62}{}_{}{}^{}+2\mathrm{}{}_0{}^{}{}_{}{}^{}n_{}^1{}_{}{}^{}$. The $n-2n$ disintegration of the deuteron has been investigated for 14-Mev neutrons and cross section found to be of the order of 9-4×${10}^{-26\mathrm{}}$ ${\mathrm{cm}}^2$. The scattering cross sections at 4.1, 12.5, and 13.5 Mev are, respectively, for H 1.73, 0.69, 0.694×${10}^{-24\mathrm{}}$ ${\mathrm{cm}}^2$; for D 1.79, 0.78, 0.864×${10}^{-24\mathrm{}}$ ${\mathrm{cm}}^2$; for C 1.99, 1.40, 1.23×${10}^{-24\mathrm{}}$ ${\mathrm{cm}}^2$. The experimental results are compared with those of other experimenters and with theoretical predictions.