STUDY OF (P,XN) REACTIONS AT 400-MEV

Cross sections for a number of (p,xn) reactions (1≤x≤4) at 400 MeV are reported. The excitation function for the Ge72(p,xn)As73-x system was measured between 100 and 400 MeV. The data are compared with the results of Monte Carlo cascade (Vegas) calculations and evaporation calculations. The experimental dependence of the As75(p,xn)Se76-x cross sections on x did not agree well with the results of these calculations, although the Vegas step calculations reproduced the shape of this dependence. The cross-section data are consistent with a mechanism involving charge-exchange p-n scatterings, within the target nucleus, followed by the evaporation of x-1 neutrons. The ratio of σ(p,2n) to σ(p,n) was found to be approximately linear with the quantity ETz*Sn. This quantity is the ratio of the excitation energy obtained if the isobaric analog state of the target is populated via the (p,n) reaction, to the neutron separation energy. On the basis of the postulated mechanism, the propability for charge-exchange scattering as a function of excitation energy was obtained for Y89 and Te126. © 1969 The American Physical Society.