Final Report of the International Project for the Calibration of Absolute Intensities in Small‐Angle X‐ray Scattering

An international intercomparison project was performed to test the reproducibility and the comparative accuracy of the various absolute intensity calibration techniques in current use in small‐angle X‐ray scattering with the participation of fifteen investigators from eight different laboratories in six countries. In the project, the absolute differential X‐ray scattering cross sections of standard samples of glassy carbon and polystyrene were calibrated using five different calibration techniques and two different X‐ray wavelengths. The results have been intercompared with a variety of statistical techniques. It is concluded that angularly dependent errors associated with determining the zero of angle, dead‐time corrections, collimation corrections, and insufficiently close data point spacing are more important in accounting for discrepancies between laboratories than are differences in the absolute intensity calibration methods themselves.