Disintegration of Aluminum by Protons in the Energy Range 0.4 to 3.0 Bev

Abstract

Excitation functions for the production of ${\mathrm{Na}}^{24}$, ${\mathrm{Na}}^{22}$, ${\mathrm{F}}^{18}$, ${\mathrm{O}}^{15}$(?), ${\mathrm{N}}^{13}$, ${\mathrm{C}}^{11}$, and ${\mathrm{Be}}^{7}$ in proton bombardments of Al have been measured from 0.4 to 3.0 Bev. The formation cross sections have strikingly small energy dependence, and this feature is discussed in the light of possible energy transfer mechanisms. The absolute cross-section values are based on a calibration method (suggested by A. Turkevich) which is discussed. It is based on measurements of gross radioactivity in copper irradiated at various energies and on the assumption that the fraction of inelastic collisions with copper nuclei that lead to radioactive products is independent of proton energy from 0.3 to 3 Bev. The validity of this assumption is examined.