Photon Scattering from Bound Atomic Systems at Very High Energy

Abstract

The elastic scattering of photons from bound atomic systems is studied in the limit of infinitely high energy. It is found that the amplitude differs significantly from the free-particle value when the binding is strong. Explicit formulas for a spin-0 particle bound in a $\frac{1}{r}$ potential (both world-scalar and Coulomb) are obtained as well as power series in the coupling strength for a spin-½ target. The general result in the latter case is reduced to quadratures.