Differential cross sections for the elastic scattering of protons by ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ and ${}_{}{}^4{}_{}{}^{}\mathrm{He}$, and for the ${}_{}{}^4{}_{}{}^{}\mathrm{He}\mathrm{}(p,d)\mathrm{}{}_{}{}^3{}_{}{}^{}\mathrm{He}$ reaction were measured at an incident energy of 85 MeV. The elastic scattering cross sections have been compared with phenomenological optical model calculations which yield good fits to the experimental data, provided that a Majorana exchange term is included in the optical potential. The ${}_{}{}^4{}_{}{}^{}\mathrm{He}\mathrm{}(p,d)\mathrm{}{}_{}{}^3{}_{}{}^{}\mathrm{He}$ data show qualitative agreement with distorted-wave Born-approximation calculations. In addition the experimental data are compared to resonating group theory calculations; one channel calculations for the elastic scattering, and two channel calculations for the ${}_{}{}^4{}_{}{}^{}\mathrm{He}\mathrm{}(p,d)\mathrm{}{}_{}{}^3{}_{}{}^{}\mathrm{He}$ reaction. These resonating group calculations are in qualitative agreement, and generally reproduce the important features of the experimental data.

NUCLEAR REACTIONS ${}_{}{}^3{}_{}{}^{}\mathrm{He}\mathrm{}(p,p)\mathrm{}$, ${}_{}{}^4{}_{}{}^{}\mathrm{He}\mathrm{}(p,p)\mathrm{}$, and ${}_{}{}^4{}_{}{}^{}\mathrm{He}\mathrm{}(p,d)\mathrm{}$, $E=85.0\mathrm{}$ MeV measured $\sigma \left(\theta \right)$, enriched targets.

• Received 11 February 1974

DOI:https://doi.org/10.1103/PhysRevC.10.520