Compton camera simulation for drift strip CdZnTe detectors

In this study, Compton camera simulation was performed using CdZnTe drift strip detector. MEGAlib data analysis and imaging program was used for the Compton camera simulations and data analysis. Simulations were performed with GEANT4 in MEGAlib. Initially, three mass models have been developed for the Compton camera, which is intended for optimum image quality. Simulations were performed by using gamma ray sources on these mass models. The results from simulations were evaluated by Compton camera performance parameters. As a result of the evaluations, mass model 1 was chosen for development and accordingly mass model 4 was formed. Mass model 4 consists of 4 silicon layers each containing 9 silicon detectors and 2 CZT layers each containing 9 CZT detectors. Simulations were performed for mass model 4 with gamma ray sources with the energy of 300, 356, 662, 1000 and 1333 keV. The mass model 4 was found to have 4.46º FWHM value for its ARM distribution at 662 keV. Finally, effective areas of mass model 4 were calculated for gamma ray sources with the energy of 300, 356, 662, 1000 and 1333 keV. The results were compared with mass model 1 effective area values. As a result of the evaluation, it was observed that the effective areas of mass model 4 show the expected increase compared to effective areas of mass model 1. It was also observed that the FWHM values of ARM distribution for photopeak energies improved compared to mass model 1. Consequently, these results showed that mass model 4 is an advantageous Compton camera prototype for a possible space mission.