Gain calibration with temperature compensation of silicon photomultipliers for cosmic ray muon imaging system

Background A liquid scintillator detector prototype employing silicon photomultipliers (SiPMs) as the readout device has been developed for cosmic ray muon imaging. The system is intended for deployment in open environments, which pose challenges for maintaining stable SiPM performance due to temperature-dependent breakdown voltage and gain fluctuations.
Purpose This study aims to ensure the stable performance of SiPMs under harsh and dynamic environmental conditions by mitigating the effects of temperature-dependent gain variations.
Methods A bias voltage adjustment based on a real-time temperature was implemented to ensure consistent gain stability. In addition, a water-cooling system was incorporated to reduce thermal noise and improve single-photon resolution under harsh environmental conditions.
Results and conclusions Experimental tests demonstrated a significant improvement in gain non-uniformity to 0.33% across all channels and stabilized performance under extreme thermal conditions up to 50℃.