Development of a Fast Detector for Associated Particle Imaging

• Main Authors: Giacomini, G., Carini, G., Chen, W., Dellapenna, A., Deptuch, G., Durando, S., Fabris, L., Fried, J., Kierstead, J., Kotov, I., Gorni, D., Guidolini-Cecato, R., Mcconchie, S., Mandal, S., Muller, E.
• Format: Conference Proceeding
• Language: English
• Subjects: Alpha particles; Generators; Neutrons; Silicon; Temperature sensors; Tomography; Vacuum systems
• ISSN: 2577-0829
• DOI: 10.1109/NSS/MIC/RTSD57108.2024.10657027

In an Associated Particle Imaging (API) neutron generator, a neutron and an alpha particle are emitted back-to-back and detecting the alpha inside the vacuum chamber will help reconstruct the trajectory of the neutron which, after escaping the chamber, can be used - for example - for tomography of a high-Z material. We are developing pixelated detectors able to accurately determine the hit position and time of the alpha particle. The first detector is based on a large area monolithic silicon sensor sitting in vacuum and read-out by an ASIC which is mounted onto a board external to the vacuum chamber. Signals from the ASICs are then processed by FPGAs placed on the same boards for timing and amplitude extraction. The second detector mounts the ASICs inside the vacuum of the neutron generator, to decrease the parasitic capacitance due to the long connections and therefore to increase the timing resolution of the system. This is a multifaceted activity which requires the development of many parts, including the silicon sensors, a vacuum-compatible assembly, a fast ASIC, a FPGA firmware among other aspects. At the conference, we will detail the status of each single part of the detector development.