Nuclear Reactions of Low-Z Elements with 5.7-Bev Protons

This work describes the results of 5.7-Bev proton bombardments of the target elements Be, C, N, O, F, Na, and Al. Production cross sections were obtained for many radioactive products with half-lives between 1.2 minutes and 2.6 years. The (p, pn) cross sections for the targets C, N, O, F, and Na were found to be 29±3 mb, 7.3±0.7 mb, 33±5 mb, 19±2 mb, and 31±5 mb, respectively. Much of the variation in these values is thought to be due to the difference in the number of neutrons available for (p, pn) reactions in the different target nuclei. The cross sections for other types of reactions studied do not change as much over the above range of target elements as do the (p, pn) cross sections. Comparison of the cross sections measured in this work with those obtained at 0.98 to 3 Bev shows that in the 1- to 5.7-Bev energy range the excitation functions are nearly constant.