Winner-Leader-Follower a Novel Hit Allocation Algorithm for Pixel Detectors

• Published in: IEEE transactions on nuclear science 2024-05, Vol.71 (5), p.1250-1256
• Main Authors: Jirsa, J., Marcisovsky, M., Janoska, Z., Jakovenko, J.
• Format: Article
• Language: English
• Subjects: Algorithms; Clustering; Clustering algorithms; CMOS; Detectors; Digital integrated circuits; Electronics; Fluorescence; Image resolution; Photonics; Photons; Pixels; position-sensitive particle detectors; radiation detector circuits; Resource management; semiconductor radiation detectors; System-on-chip; X-ray detectors; X-ray imaging
• ISSN: 0018-9499; 1558-1578
• DOI: 10.1109/TNS.2024.3378002

The integration of front-end electronics into pixel electronics enables hybrid pixel detectors to capture a high-resolution X-ray image. The decreasing size of the technology node allows pixel electronics to integrate in tens of micrometers of pixel pitch. On the other hand, the decreasing pixel pitch size leads to new problems, such as the charge-sharing effect and fluorescent photons in high-Z materials. These effects decrease the spatial and spectroscopic resolution of the detectors. This article presents a novel asynchronous hit allocation algorithm, Winner-Leader-Follower (WLF). The proposed algorithm operates in the digital domain and performs clustering and hit allocation within 5 \times 5 pixels. The algorithm's concept and implementation are presented, followed by measurements obtained with a test chip designed in a 65-nm complementary metal-oxide semiconductor process.