FINAL-STATE INTERACTIONS IN COLLISIONS OF AN ATOM AND A DIATOMIC MOLECULE

The distorted-wave Born approximation (DWBA) with a semiclassical (WKB) description of relative translational motion is used to characterize final-state interactions in the collision of an atom with a diatomic molecule. The resulting cross section is found to be the product of one factor that varies slowly with energy and another which characterizes the final-state interaction. This latter factor, containing the resonant-type of energy dependence, is determined solely by the distorting potential, being independent of the interaction producing the given transition. Simple physical interpretations and useful extensions are obtained by employing the concept of time delay.