Modeling of proton-induced radiation damage in pixelated CdZnTe detectors for space

The 3D position sensitive pixelated CdZnTe(CZT) detector is considered one of the most promising detector for modern space Compton telescopes. However, detectors operating in space orbit will possibly experience a deterioration in its performance due to the accumulation of proton-induced radiation damage. Although adequate ground-based radiation experiments on CZT have been done so far, there is still a lack of detailed theoretical modeling and effective simulation methods for the radiation damage of CZT detectors in space. Under the theoretical framework of solid-state physics and Monte Carlo simulation, a physical model was developed to quantitatively evaluate the radiation damage of CZT detector depending on the orbital characteristics and design lifetime of the satellite. This study can be used to optimize the design of Compton telescopes that employ pixelated CZT and provide possible strategies for improving the radiation hardness of CZT detectors for space missions. The model has been applied to simulate some published CZT detector radiation experiments and the results were compared, showing good agreement. But considering the different electrode structures and the properties of CZT detectors in these experiments, proton radiation experiments on pixelated CZT detectors will be carried out to verify the validity of the model.