Design of a ZnO:Ga/SiPM array alpha detector for associated particle imaging

A compact associated alpha detector based on a ZnO:Ga scintillator coupled to a 121-channel SiPM array was proposed for associated particle imaging (API) applications. Monte Carlo simulations were performed to evaluate the detector response, position reconstruction capability, and timing performance. The simulation results show that scintillation light is shared among several neighboring SiPM channels, providing sufficient information for position and timing reconstruction. Position reconstruction was investigated using the COG method together with two-dimensional correction and CNN-based correction methods, achieving a spatial resolution better than 0.6 mm over most of the effective detection area. The timing performance was evaluated using an amplitude-weighted timing method combined with time-walk and flight-distance corrections, resulting in a timing resolution of 81.5 ps. These results demonstrate the feasibility of the proposed detector concept and indicate that it is a promising SiPM-based solution for high-resolution API applications.