Methods of Treating Coulomb Interference Corrections in Potential Scattering

Three distinct, though related, formalisms, developed by Block, by West, and by Auvil, for dealing with Coulomb interference corrections to nuclear potential scattering problems are considered. Such formalisms are particularly relevant to the analysis of recent pion-helium scattering experiments, and their equivalence is examined. It is shown that to first order in the Coulomb coupling parameter $n$, the results for the scattering amplitudes given by West and by Auvil (as generalized in the present work) are equivalent but differ from those suggested by Block. On the other hand, to first order in $n$ the results for the cross sections are all seen to be equal.