Coulomb effects on the singularities of charged particle exchange scattering amplitudes are discussed. It is shown that the nature of the exchange singularity depends on the value of $\eta$ and that the amplitude is finite for $\eta >1\mathrm{}$. Coulomb correction factors which include the effects of Coulomb distortion are given for a suitably defined exchange pole residue in the cross section. The implications of these results on determinations of the asymptotic $D$- to $S$-state ratio in the deuteron, ${}_{}{}^3{}_{}{}^{}\mathrm{H}$, and ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ are discussed.

NUCLEAR REACTIONS Coulomb corrections in charged particle exchange amplitudes.

• Received 11 March 1981

DOI:https://doi.org/10.1103/PhysRevC.24.1379