Development of plastic scintillators with SiPM readout for satellite-borne astroparticle physics experiments

Space is a privileged place for gamma-ray observation. The MeV – GeV region remains poorly covered due the intrinsic difficulties in the detection techniques. Many astrophysical sources, e.g. Gamma-Ray Bursts (GRBs), have the bulk of their emission in this energy range, pointing out the need for improved observations in this energy range. The goal for future telescopes is to operate in both Compton and pair conversion regimes. Technological advancements in recent years in double-sided Si strip detectors (DSSDs) and Silicon Photomultipliers (SiPMs) offer new solutions for satellite-based experiments. In this work I focused on the development of plastic scintillator detectors with SiPM readout, to be used in tracking detectors. I describe the development of a scintillting Fiber TracKer (FTK) in the context of the NeUtrino and Seismic Electromagnetic Signals (NUSES) mission. NUSES is a pathfinder satellite for SiPM-based detectors in space. In this work I characterized several prototypes with a custom front-end board. I also conducted several studies on the board itself and the electronics. The results of these studies include the best fiber-readout geometry for the Ziré FTK, given the detector requirements, they demonstrate the capability of the FTK to provide a fast and efficient (> 98%) trigger and a space resolution of ∼ 300 μm. In the second part of this work, I focused on studying GRB221009A with the Fermi-Large Area Telescope (LAT). This GRB stands out for its extreme brightness and unique characteristics, including a high-energy triggering pulse and a possibly early onset of its afterglow. The high-energy emissions challenge the conventional explanation based on synchrotron radiation, hinting at the presence of extra components. Additionally, we observed a narrow MeV line in this GRB, offering valuable insights into GRBs, highlighting the importance of future MeV – sensitive detectors for uncovering more of these distinctive features.