We have developed a computer program for PIXE tomographic reconstruction of trace elemental distributions using the maximum-likelihood expectation-maximization (MLEM) algorithm. This algorithm is based on the exact stochastic model of X-ray yield measurements. Energy loss of the incident particles and attenuation of the X-ray photons are incorporated into the reconstruction algorithm so quantitatively accurate trace elemental concentrations can be obtained. The reconstruction algorithm has been tested using calculated X-ray yields generated from a micro-PIXE line scan simulation program. This algorithm is capable of reconstructing elemental distributions using only four angular views of the sample. © 1995.
Liew, S. C., Orlic, I., & Tang, S. M. (1995). PIXE tomographic reconstruction of elemental distributions using an iterative maximum-likelihood method. Nuclear Inst. and Methods in Physics Research, B, 104(1–4), 222–227. https://doi.org/10.1016/0168-583X(95)80093-X