NUCLEAR REACTIONS OF LOW-Z ELEMENTS WITH 5.7-BEV PROTONS NUCLEAR STRUCTURE AND SIMPLE NUCLEAR REACTIONS (thesis)

Abstract

The results of 5.7-Bev proton bombardments of the target elements Be, C, N, O, F, Na, and Al are described. Production cross sections were obtained for many radioactive products with half lives between 1.2 minutes and 12 years.The p,pn cross sections for the targets C, N, O, F, and Na were found to be 29 er inch per 3, 7.3 er inch per 0.7, 33 er inch per 5, 19 er inch per 2, and 31 er inch per 5 mb, respectively. Much of the variation in these values is shown 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 range of target elements studied as do the p,pn cross sections. Extension of the excitation functions for the reactions studied up to 5.7 Bev shows that the cross sections seem to be fairly constant between 1 to 3 Bev and 5.7 Bev. A theory is developed to describe the observed magnitude and variation of the cross sections for simple nuclear reactions as exemplified by the p,pn reaction. At multi-Bev energies to which thismore » treatment is restricted, the main contribution to the p,pn- reaction cross section comes from inelastic collisions between the incldent protons and target neutrons, with all the p-n collision products escaping without further interaction. (auth)« less