Optimization of GEM detectors for applications in X-ray fluorescence imaging

TL;DR

This paper presents simulations to optimize gaseous detectors for X-ray fluorescence imaging, focusing on energy resolution and design improvements to reduce escape peaks and account for fluorescence effects.

Contribution

It introduces a simulation-based approach to optimize GEM detector design and performance for X-ray fluorescence imaging in the 3-30 keV range.

Findings

Energy resolutions of 15.4% for Ar/CO₂ and 14.6% for Kr/CO₂ at 6 keV.

Detector design modifications can reduce escape peaks.

Modeling of copper fluorescence helps improve detector accuracy.

Abstract

In this work a set of simulations that aim at the optimization of gaseous detectors for applications in X-ray fluorescence imaging in the energy range of 3 -- 30keV is presented. By studying the statistical distribution of the radiation interactions with gases, the energy resolution limits after charge multiplication for 6keV X-ray photons in Ar/CO$_2$(70/30) and Kr/CO$_2$(90/10) were calculated, obtaining energy resolutions of 15.4(4)% and 14.6(2)% respectively. The detector design was also studied to reduce the presence of escape peaks and complement a model to evaluate the inevitable X-ray fluorescence of copper generated by the conductive materials inside the detector.