At 0.6 and 3 GeV, cross sections for the production of ${}_{}{}^3{}_{}{}^{}\mathrm{H}$, ${}_{}{}^3{}_{}{}^{}\mathrm{He}$, and ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ in C and Si were determined, and for the production of ${}_{}{}^3{}_{}{}^{}\mathrm{H}$ and ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ in oxygen. At 33 GeV only ${}_{}{}^3{}_{}{}^{}\mathrm{H}$: ${}_{}{}^3{}_{}{}^{}\mathrm{He}$: ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ production ratios in C and Si could be established due to a fault in the monitoring. The ${}_{}{}^3{}_{}{}^{}\mathrm{H}$/${}_{}{}^3{}_{}{}^{}\mathrm{He}$ yield of 0.85±0.10 embraces the three target materials throughout the energy range investigated. On the other hand, the ${}_{}{}^4{}_{}{}^{}\mathrm{He}$/${}_{}{}^3{}_{}{}^{}\mathrm{He}$ ratios varied with energy and with target material by up to a factor of 2. Most of the previous ${}_{}{}^3{}_{}{}^{}\mathrm{H}$ cross-section determinations in carbon are shown to be low by a factor of 2 or 3, apparently because of tritium diffusion from the thermoplastic materials used in the earlier studies. The majority of ${}_{}{}^3{}_{}{}^{}\mathrm{H}$ cross sections at 600 MeV in targets from helium to bismuth fit the equation $\sigma \mathrm{}\left(A\right)=30\mathrm{}\exp \left(\frac{A}{100}\right)$, which should be beneficial in predicting unknown cross sections. A trend in the ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ cross sections as a function of target mass was discernable, but the scatter of the data does not permit making a more detailed examination; no ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ trend as a function of $A$ is observed.

• Received 31 March 1971

DOI:https://doi.org/10.1103/PhysRevC.7.2179