A comparison of the neutron detection efficiency and response characteristics of two pixelated PSD-capable organic scintillator detectors with different photo-detection readout methods

We characterize the performance of two pixelated neutron detectors: a PMT-based array that utilizes Anger logic for pixel identification and a SiPM-based array that employs individual pixel readout. The SiPM-based array offers improved performance over the previously developed PMT-based detector both in terms of uniformity and neutron detection efficiency. Each detector array uses PSD-capable plastic scintillator as a detection medium. We describe the calibration and neutron efficiency measurement of both detectors using a ${}^{137}$Cs source for energy calibration and a ${}^{252}$Cf source for calibration of the neutron response. We find that the intrinsic neutron detection efficiency of the SiPM-based array is ($30.2\pm 1.7$)%, which is almost twice that of the PMT-based array, which we measure to be ($16.9\pm 0.2$)%.