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arXiv · 2011.03542

X-ray dark-field signal reduction due to hardening of the visibility spectrum

Fabio De Marco·Jana Andrejewski·Theresa Urban·Konstantin Willer·Lukas Gromann·Thomas Koehler·Hanns-Ingo Maack·Julia Herzen·Franz Pfeiffer
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Abstract

X-ray dark-field imaging enables a spatially-resolved visualization of ultra-small-angle X-ray scattering. Using phantom measurements, we demonstrate that a material's effective dark-field signal may be reduced by modification of the visibility spectrum by other dark-field-active objects in the beam. This is the dark-field equivalent of conventional beam-hardening, and is distinct from related, known effects, where the dark-field signal is modified by attenuation or phase shifts. We present a theoretical model for this group of effects and verify it by comparison to the measurements. These findings have significant implications for the interpretation of dark-field signal strength in polychromatic measurements.

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Fabio De Marco, Jana Andrejewski, Theresa Urban, Konstantin Willer, Lukas Gromann, Thomas Koehler, Hanns-Ingo Maack, Julia Herzen, Franz Pfeiffer. 2020-11-06. X-ray dark-field signal reduction due to hardening of the visibility spectrum. https://arxiv.org/abs/2011.03542

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