Differential cross sections for the elastic scattering of various hydrogen and helium isotopes have been measured using accelerated particles from the Los Alamos 42-inch cyclotron. The scattering of protons and deuterons from deuterons, tritons, and helium-three particles has been studied over an energy range of 5 to 14 Mev. The elastic scattering of ∼10-Mev polarized protons has also been studied. In all cases nuclear emulsions were used as detectors.

Proton-deuteron elastic scattering has been measured at 5.6 and 7.85 Mev. A comparison is made to results at nearby energies of both $p-D$ and $n-D$ scattering and to theoretical predictions. The scattering of 10-Mev polarized protons from deuterons has been measured and provides support for calculations using central force approximations.

Measurements of $p-T$ and $p$-${\mathrm{He}}^3$ elastic scattering at 6.5 and 8.34 Mev give angular distributions which are quite similar to those for $p-D$ and $p$-${\mathrm{He}}^4$. An encouraging agreement is found with resonating-group calculations with central-force approximations of the Serber type.

Deuteron-deuteron scattering has been measured at 6.0, 8.2, 12.1, and 13.8 Mev. A preliminary theoretical treatment indicates that the process is predominantly hard-sphere scattering with no strong level splitting.

Deuteron-triton and deuteron-helium three scattering has been measured over the energy range of 5 to 14 Mev. The results for the two processes are almost indistinguishable at the present level of accuracy.

• Received 28 September 1959

DOI:https://doi.org/10.1103/PhysRev.117.1307