Characterization of an LSO scintillator for space applications

Abstract

Currently BGO (Bi4Ge3O12) is widely used for the detection of high-energy particles in space applications because of its high stopping power, the non-hygroscopic characteristics and its ruggedness with respect to mechanical stress. The new Cerium doped LSO (Lu2SiO5) offers the same benefits with higher light output capabilities and a significantly shorter decay time. We investigated key characteristics of an LSO scintillator in view of its use in space missions. We characterized the intrinsic spectrum which originates from the decay of 176Lu and showed that it consists of three different parts arising from different effects: the native intrinsic spectrum, chance coincidence effects and energy deposition in the readout photodiode. Furthermore we investigated the light-quenching of LSO for heavy ions with measurements performed at the Heavy Ion Medical Accelerator in Chiba (HIMAC), Japan. We found that LSO is a promising candidate for future space missions.