Characterisation of the readout electronics of the Si(Li) tracker for the first flight of the GAPS experiment

According to what is supported by some astrophysics theories, about 90% of the mass of the universe is made by a hypothetical form of matter named Dark Matter and its discovery is one of the main scientific objectives of the 21st century in the field of physics research. Dark Matter is not directly observable, since, unlike normal matter, it does not emit electromagnetic radiation and only manifests itself through gravitational effects. In this context, the General Antiparticle Spectrometer project stands as a modern approach for the indirect search of Dark Matter through the detection of cosmic antideuterium. The experiment relies on two detectors: a time-of-flight system, which tags candidate events for the detector to save and makes a precise velocity measurement, and a tracker system based on lithium-drifted silicon detectors, which serves as the target and tracker for the initial cosmic-ray particle and its annihilation products. An Application Specific Integrated Circuit called SLIDER32 designed in a commercial 180 nm CMOS technology is currently employed for the readout of the lithium drifted silicon detectors and will be used for the first flight of the experiment foreseen for late 2023. This thesis work describes the characterisation work that has been carried out on the flight items of the lithium-drifted silicon tracker and includes an in-depth description of the validation techniques used for all detector components and the results obtained during the testing process. The characterisation process of the SLIDER32 integrated circuit at varying temperatures and the corresponding performed measurements are also reported, with an indication of their impact on the overall performance of the instrument. Finally, the thesis work presents the results obtained during the experimental activity regarding an innovative approach to cosmic muon detection through the coincident use of an ionising radiation detector and a fully assembled lithium-drifted silicon tracker module, the first one acting as a trigger for the tracker readout electronics.