Abstract
In our previous work, a cost-effective Compton camera (CC) using Ce doped Gd3(Al,Ga)5O12(Ce:GAGG) scintillator consisting of two detectors, scatterer (20.8 × 20.8 × 5 mm3) and absorber (41.7 × 41.7 × 10 mm3), was developed to image gamma rays having energy more than 511 keV. This study fabricated a newly developed CC with a larger scatterer and thinner absorber. The system consists of two detectors: a scatterer and an absorber of Ce:GAGG scintillator. The size of the scatterer and absorber is the same; a 40-mm × 40-mm × 5-mm array block consists of 40 × 40 pixels. The size of each scintillator pixel is 0.85 mm × 0.85 mm for both systems. Imaging experiments of Na-22 and Cs-137 point sources were performed to investigate the imaging capability of the new camera, and then the obtained data were compared to the previous CC. The current CC's absolute detection efficiency (DEa) and photopeak detection efficiency (DEp) are improved by 1.6 and 2 times greater than the previous one. At the same time, both systems' spatial and angular resolutions are almost the same value at 511 keV. The Compton camera module (CCMod) in GATE v9.0 was employed for Monte Carlo simulations to reproduce the experimental data showing a good agreement.