Impact of Photon Transport Properties on the Detection Efficiency of Scintillator Arrays

For spatially resolved X- and gamma ray detection pixelated scintillator arrays are used. In this study we simulate the quantum gain process of a scintillator array and its impact on the detective quantum efficiency of the detector system. The simulation tool comprises a full physical Monte-Carlo model of the X-ray interactions as well as the transport processes of the scintillation photons within the detector system. As an example, we analyze an Gd₂O₂S:Pr scintillator array with typical 1 mm pixel pitch and TiO₂ based reflective material. The results indicate that for integrating systems fluorescence escape effects play a major role in the noise performance of scintillating pixel detectors. Additionally, the light generation and transport processes can have an impact on the signal-to-noise ratio.