Particle-wave ambiguities in the interpretation of heavy-ion reactions

The relations between the partial wave scattering amplitudes in l-space and the reaction cross section angular distributions are derived in the limits of classical and diffractive scattering. It is shown that a measurement of the angular distribution of a “quasi-elastic” heavy ion reaction does not permit an unambiquous inference of the reaction's partial-wave amplitudes, even for large l. The ambiguities are illustrated with DWBA calculations.