Cross Sections for Products of 90-Mev Neutrons on Carbon

Determinations have been made of the cross sections for the products of 90-Mev neutrons on carbon in the case of practically all reactions that occur. Beta-counting of the activities generated in a rotating polyethylene disk yielded cross sections for the production of some heavy fragments, identified as to isotope and atomic number. Cloud-chamber study yielded cross sections for almost all reactions, but resulted in the identification of most of the heavy fragments only by atomic number. The rotating disk method cross sections were normalized to the ${\mathrm{C}}^{12}(n; 2n){\mathrm{C}}^{11}$ cross section, and the cloud-chamber method cross sections were normalized to the $n-p$ cross section.