Testing and Analysis of PICOSEC MicroMegas Precise Timing Detectors

Today’s high energy physics experiments require precise timing detectors to enable accurate track reconstruction and identification of vertices from which particles originated. The PICOSEC collaboration is developing a MicroMegas based detector aimed at achieving high precision timing performance, currently showing results in the range of tens of picoseconds. The GDD team at CERN has designed and built multiple prototypes of the PICOSEC detector with goals of achieving large scalability, optimizing timing resolution and improving robustness. These prototypes, including a single channel detector and a 100 channel resistive detector, were tested and analyzed during the July 2022 test beam campaign which utilized CERN’s Super Proton Synchrotron H4 beam line as a muon beam source. This work outlines the methodology of stability and operation testing completed on the 100 channel resistive PICOSEC prototype in preparation for the test beam. The detector showed stability to anode and cathode voltages of 711 V and -809 V, respectively, and proper response to a photon source. It also describes the single photoelectron and muon beam measurements taken at the test beam with a single channel PICOSEC prototype, and post test beam analysis for studies of the number of photoelectrons generated at the photocathode. The electron peak amplitude spectrums from single photoelectron runs were Polya distributed. The Polya fits on the spectrums from muon beams showed poor goodness of fit due to events occurring outside of a 2 mm radius of the detector’s center, where the full 6 mm diameter Cherenkov cone is not incident on the photocathode. Tracking data from the test beam telescope’s GEM tracking system should be used to veto events outside the center region of the detector for future analysis.