WE-G-103-02: DQE of CsI Microcolumnar X-Ray Detectors Using Hybridmantis and Lubberts' Formulation

Abstract

Purpose: We describe a method to study the detective quantum efficiency (DQE) performance of CsI microcolumnar CsI x-ray detectors using hybridmantis, an approach for Monte Carlo simulations that maximizes utilization of CPUs and GPUs within modern workstations. Methods: We use hybridmantis, which is a modified version of penelope that outputs coordinates and energy deposited during x-ray and electron interactions occurring within the scintillator which are then used as source for optical showers using fastdetect2. We make use of the Lubberts description of the scintillator as a stack of thin layers and calculate the transfer of noise and signal as the weighted summation of the contribution of each layer. Results: We show results in terms of the Lubberts fraction and then report DQE by introducing the Swank factor and the x-ray interaction efficiency calculated from the Monte Carlo output. We report DQE results calculated using our methods for 4 screen models previously studied by our group. Conclusion: This method relies on the calculation of point response functions at each depth and proper weighting of the contribution of each layer to signal and noise transfer. This methodology can be used to guide optimization approaches for maximizing DQE of microcolumnar CsI x-ray detectors.