Impulse approximation in the peripheral region

Abstract

We show that the peripheral part of the elastic scattering impulse approximation can be expressed entirely in terms of on-shell information. The impulse approximation is given in terms of an integral over the onshell elementary amplitude. We find the range of energies required in that amplitude for the peripheral part and discuss the closure approximation to this integral.NUCLEAR REACTIONS Scattering theory, low density limit of the impulse approximation. Application to $\ensuremath{\pi}$-nucleus scattering and $K$-mesonic atoms.