Multi-energy X-ray tomography is studied for decomposing three materials using three X-ray energies and a classical energy-integrating detector. A novel regularization term comprises inner products between the material distribution functions, penalizing any overlap of different materials. The method is tested on real data measured of a phantom embedded with Na2SeO3, Na2SeO4, and elemental selenium. It is found that the two-dimensional distributions of selenium in different oxidation states can be mapped and distinguished from each other with the new algorithm. The results have applications in material science, chemistry, biology and medicine.
@article{arxiv.2309.04479,
title = {Inner product regularized multi-energy X-ray tomography for material decomposition},
author = {Salla-Maaria Latva-Äijö and Filippo Zanetti and Ari-Pekka Honkanen and Simo Huotari and Jacek Gondzio and Matti Lassas and Samuli Siltanen},
journal= {arXiv preprint arXiv:2309.04479},
year = {2025}
}