Phase Contrast X-Ray Microscopy — Experiments at the BESSY Storage Ring

Up to the end of 1986 it was always stated that to a good approximation soft x-ray photons participate in only one reaction with matter, i.e. absorption of the photon in an atom, because the atomic cross sections for inelastic and elastic scattering are 4 to 5 orders of magnitude smaller than the atomic cross section for photoelectric absorption. But this is only half the truth.