Results for the atomic elastic scattering of photons of 59.54 keV lying in the vicinity of K-absorption edges of rare earths ${(}_{68}$Er and ${}_{70}{}^{}{}_{}{}^{}\mathrm{Yb}$) are presented. An assessment of all existing experimental results published in the last few years has been made in terms of some of the most important calculations on photon–bound-electron collisions as a function of photon energy and momentum transfer that have been developed in the 1980s. The analysis presents the trend of behavior of the theoretical cross section as the incident photon energy crosses the K-shell photoionization thresholds of the scattering atomic system.

• Received 28 August 1989

DOI:https://doi.org/10.1103/PhysRevA.41.5869