Silicon Photomultipliers Detectors For Next Generation High-Energy Space Telescopes

Photon detection is a central element of any high-energy astronomy instrumentation. One classical setup that has proven successful in many missions is the combination of photomultiplier tubes (PMTs) with scintillators, converting incoming high-energy photons into visible light, which in turn is converted in an electrical impulse. Although being extremely sensitive and rapid, PMTs have the drawback of being bulky, fragile, and require a high-voltage power supply of up to several thousand volts. Recent technological advances in the development of silicon photomultipliers (SiPM) make them a promising alternative to PMTs in essentially all their applications. We have started a R&D program to assess the possibility of using SiPMs for space-based applications in the domain of high-energy astronomy. We will present results of our characterization studies of SiPMs from 3 manufacturers. Each SiPM detector has been tested inside a dedicated vacuum chamber and at low temperature to assess its performance in a representative space environment. Irradiation tests are scheduled to understand the susceptibility of SiPM to radiation damage. After comparison, we will select a baseline detector and design a specific front-end electronics and mechanical system. Furthermore, we plan to develop a low noise voltage power supply that ensures the stability of the SiPMs and to study their coupling to scintillators. Finally, our ultimate goal is to qualify the system for a space Technical Readiness Level of 5.