[15a-D209-1~10] 2.3 Application, radiation generators, new technology

[15a-D209-4] Simulation-Based Performance Evaluation of an therapeutic Ion-Beam Imaging System Using a Fine-Pitch CdTe Imager Measuring Prompt X-ray

〇Mitsutaka Yamaguchi¹, Yuto Nagao¹, Shinichi Gotoh², Naoki Kawachi¹ (1.QST Takasaki, 2.GO PROTON JAPAN Inc.)

Keywords:CdTe imager, radiation imaging, prompt X-ray

We evaluated spatial resolution and sensitivity of an therapeutic ion-beam imaging system using a fine-pitch cadmium telluride (CdTe) imager measuring secondary electron bremsstrahlung by Monte Carlo simulations. The simulations were performed by PHITS 3.10. The geometrical setup of the simulation consisted of a water phantom irradiated by ion beams and a pinhole-type X-ray camera. The water phantom comprised a ceiling-opened container with water inside. The X-ray camera was composed of a tungsten shield having a pinhole collimator and a board of CdTe having the size of 2 cm × 2 cm × 0.04 cm, which was partitioned into 50 × 50 pixels. It was found that the spatial resolution could be significantly improved by using the fine pitch imager when the the pinhole diameter was small. We will present the simulation results of spatial resolutions and sensitivities of the X-ray camera for some pinhole diameters for proton and carbon ion beams. The potential for the imaging of therapeutic ion beams will be discussed.