Simulation of X-ray fluorescence computed tomography imaging scanner based on gaseous detectors

Gaseous detectors offer an attractive alternative to commonly used semiconductor detectors in X-ray Fluorescence Computed Tomography (XFCT) systems, mainly due to their potential for large active areas and lower cost. In this work, a novel concept of XFCT imaging was investigated through Monte Carlo simulations using the GATE software. The simulated system integrates a collimation-based optical system and a position and energy-sensitive gaseous detector, filled with krypton gas, for fluorescence photon detection. Three phantoms with different geometries, sizes, elemental compositions, and attenuation conditions were simulated to evaluate the system’s capability. The results demonstrate the ability of the system to discriminate multiple elements and to reconstruct cross-sectional and three-dimensional elemental images, confirming the feasibility of XFCT imaging based on gaseous detectors. These findings highlight the potential of this approach as an alternative to semiconductor-based XFCT systems, supporting further optimization and experimental validation.