A position-sensitive scintillation detector for low-energy gamma-rays

Abstract Precise evaluation of a gamma-ray’s interaction position in scintillator detectors is important for their application in medical and industrial imaging. Two approaches can be pursued in achieving this goal: pixelated detectors or monolithic detectors coupled to pixelated readouts. Here, we present the design of a thin monolithic position-sensitive detector for low-energy gamma-rays. Two distinct position-evaluation methods were developed and assessed in terms of accuracy, precision, and imaging capabilities. An analytical model based on a curve-fitting procedure established a performance baseline. A neural network model showed superior performance, offering notable improvements in both accuracy and precision. Qualitative evaluation of the imaging results provided insights into the inherent advantages and limitations of both models. The results demonstrate the ability of a thin monolithic scintillator detector to generate images that significantly surpass the resolution of the readout array for low-energy gamma-ray imaging.