A Dirac equation optical model calculation with a relativistic Majorana exchange potential is used to represent the large angle diffraction structure observed in the 788 MeV $p$-${}_{}{}^4{}_{}{}^{}\mathrm{He}$ cross section data.

NUCLEAR REACTIONS ${}_{}{}^4{}_{}{}^{}\mathrm{He}$($p$,$p$), $E=788\mathrm{}$ MeV; calculated $\sigma \left(\theta \right)$, $A\left(\theta \right)$, and $Q\left(\theta \right)$ from relativistic optical model. Relativistic Majorana exchange potential, large angle scattering.

• Received 7 August 1979

DOI:https://doi.org/10.1103/PhysRevC.21.1899