“…They examined attenuation coefficients for elements Si, Cu, Zn, Ag, Mo, Sn and Au with generally an overall five-fold improvement in measurement accuracy (typically to within 0.1-0.2%) with respect to earlier work. This has allowed, for the first time, a critical analysis of the available theories, generally extending from the K edge of each element and upward in energy; coefficients immediately below the K edge for Ag [23], Mo [24], Cu [25] and Zn [26] were also included. Another consideration made was to incorporate measurement energy spacings at close enough increments near the K edges to show fine structure detail.…”