Non-local potentials and two-body scattering

Abstract
It is shown that in elastic collisions between spinless particles a non-local, i. e. velocity dependent, potential is uniquely determined by the knowledge of the scattering amplitude for all angles and a range of energies, provided the potential is assumed to be of a form discussed by Wong (which means that, in a certain sense, it has no explicit dependence on angular momentum) and also subject to certain, rather weak, restrictions on the analytic properties of the potential. The case of spin ½ particles is also discussed briefly.