Radiation Effects on a Potential Scintillation-Based Solid-State Spectrometer Prototype for Compact Monitoring of Space Radiation/Weather Satellite Conditions

Abstract

New and emerging scintillators, such as DPA (Diphenylanthracene) and CLYC (Cs2LiYCl6:Ce), coupled with Solid-State Photomultipliers (SSPM) provide a lightweight, low voltage, potentially radiation hard spectrometer for real-time monitoring of space weather conditions. This paper presents the results from proton radiation-hardness tests conducted for candidate scintillators and for individual cells of 1 cm2 SSPMs. Decreases from original light outputs were observed for samples of DPA and CLYC by 4% and 28% respectively with a dose of 1 kGy . Following 1 kGy exposure to the SSPMs, the dark current increased by a factor of ~ 32 for a reverse bias of 30 V. The effects of room temperature annealing on the dark current were also monitored. Decreases in quantum efficiency (22% for 420 nm and 7% for 535 nm) and light response (33% for 420 nm and 26% for 535 nm) were observed as a possible result of the formation of surface recombination-generation centers. The energy resolution of a LYSO scintillator sample coupled with a SSPM and measured for a 22Na gamma source (E = 511 kev) decreased from 15% pre-irradiation to 34% post 1 kGy irradiation.