ABSTRACT
The standard impulse approximation (IA) is chiefly based upon the following two assumptions. Only the projectile nuclear charge ZP plays an active role in the perturbation of the target T, whereas ZT remains passive and merely furnishes the initial electronic distribution of the electrons to be captured and/or ionized and the multiple scattering effects are neglected altogether. The intrinsic significance of the ameliorations of the RIA over the IA from the viewpoint of formal concept of scattering is the basis of the necessary reliability test of the theory. This is, however, insufficient since the validity of any intrinsically coherent and self-contained theoretical model in physics is considered as established with certainty only when successfully tested against measurements.
