Sci-Sat AM (1) General-05: Measurement of Coherent Scattering Form Factors using Polychromatic X-Ray Sources and Imaging Detectors

Abstract

A method of measuring coherent scattering form factors using polychromatic x-ray spectra and an energy insensitive imaging detector is developed. We show that the coherent scattering process can be formulated as a matrix equation and that the equation can be inverted to recover the coherent scattering form factor. We show that the model reproduces the known behaviour in the case of a monochromatic spectrum and demonstrate the extraction of the form factor via numerical simulations of the small angle scatter image of a small sample of water and two different x-ray spectra: a rectangular spectrum in the range 25 – 45 keV and a realistic 50 kVp spectrum from the tungsten anode of a clinical x-ray tube. Good agreement between the extracted and original form factor is obtained, although the quality of the extracted form factor can be strongly affected by the shape of the incident spectrum and the presence of noise in the scatter image. Further study is required to fully understand the physical and numerical limitations. The method could allow accurate measurements of coherent scattering form factors using clinical hardware.