Spallation of Yttrium by 240-Mev Protons

The individual cross sections of 36 nuclides resulting from the inelastic interaction of 240-Mev protons on yttrium were determined. The results were found to be in agreement with the current theories of high-energy nuclear reactions. By means of interpolated cross sections for the stable nuclei produced in the reactions, it was possible to estimate the total inelastic cross section for yttrium with 240-Mev protons. By use of this value and application of the optical model, $r_0$ for ${\mathrm{Y}}^{89}$ was found to 1.21×${10}^{-13\mathrm{}}$ cm and the nuclear transparency about 17%.