The PICOSEC-Micromegas (PICOSEC-MM) detector is a novel gaseous detector with precise timing resolution in experimental measurements. The main idea is to eliminate the time jitter produced by charged particles in ionization gaps by exploiting extreme UV Cherenkov light emitted in a crystal, which is then detected by Micromegas photodetector using an appropriate photocathode. The proof of concept of such detectors was achieved by singlechannel prototypes in muon beams of 150 GeV/c, resulting in a timing resolution of 25 ps, a performance surpassing by two orders of magnitude the best resolution reached by gaseous detectors. Using the PICOSEC-MM detector in experimental measurements of high-energy physics means building robust and efficient prototypes with a modular design.
This work focuses on developing and characterizing resistive multi-pad PICOSEC-MM prototypes, targeting their integration into the ENUBET (Enhanced NeUtrino BEams from kaon Tagging) project. ENUBET requires precise time-tagging capabilities for both electrons and muons, as well as for electromagnetic showers, to enable lepton identification at the singleparticle level. Key developments in this R&D program include investigating novel resistive layouts, scalable electronics, and robust photocathodes such as Boron Carbide (B4C), which proved resilient under beam conditions.
Among the several 7-pad resistive prototypes tested, the best-performing device—based on 10 MΩ regular resistive sharing—achieved 23 ps timing resolution under optimal conditions and retained 26 ps even during charge-sharing events. Furthermore, this prototype was the first to undergo a dedicated spatial resolution study, reaching 1.2 mm precision in both X and Y directions. These results can prove that the suggested detector technology is suitable for embedding in the hadron damp after a few radiation lengths of the absorber for muon monitoring.
Under realistic operating conditions, concerning tagging electromagnetic showers, it demonstrated 30 ps timing resolution per single cell, confirming the robustness of the B4C photocathode and resistive This enables the detector to be used as a part of an electromagnetic calorimeter for the ENUBET Application.
This dedicated R&D effort culminated in the design of a 96-pad demonstrator, developed to prove the scalability and performance of the technology for ENUBET. This large-area prototype introduced alternative board planarity and modularity solutions, achieving sub-40 ps timing resolution per cell. These results validate the feasibility of precision lepton timing in a high-rate environment and lay the groundwork for implementing PICOSEC-MM detectors in monitored neutrino beams.