Correction of beam hardening in X-ray radiograms

Baur M, Uhlmann N, Pöschel T, Schröter M (2019)


Publication Type: Journal article

Publication year: 2019

Journal

Book Volume: 90

Journal Issue: 2

DOI: 10.1063/1.5080540

Abstract

The intensity of a monochromatic X-ray beam decreases exponentially with the distance it has traveled inside a material; this behavior is commonly referred to as Beer-Lambert's law. Knowledge of the material-specific attenuation coefficient mu allows us to determine the thickness of a sample from the intensity decrease the beam has experienced. However, classical X-ray tubes emit a polychromatic bremsstrahlung-spectrum. And the attenuation coefficients of all materials depend on the photon energy: photons with high energy are attenuated less than photons with low energy. In consequence, the X-ray spectrum changes while traveling through the medium; due to the relative increase in high energy photons, this effect is called beam hardening. For this varying spectrum, the Beer-Lambert law only remains valid if mu is replaced by an effective attenuation coefficient mu(eff) which depends not only on the material but also on its thickness x and the details of the X-ray setup used. We present here a way to deduce mu(eff)(x) from a small number of auxiliary measurements using a phenomenological model. This model can then be used to determine an unknown material thickness or in the case of a granular media its volume fraction. Published under license by AIP Publishing.

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How to cite

APA:

Baur, M., Uhlmann, N., Pöschel, T., & Schröter, M. (2019). Correction of beam hardening in X-ray radiograms. Review of Scientific Instruments, 90(2). https://dx.doi.org/10.1063/1.5080540

MLA:

Baur, Manuel, et al. "Correction of beam hardening in X-ray radiograms." Review of Scientific Instruments 90.2 (2019).

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