Single photoelectron time resolution studies of the PICOSEC-Micromegas detector

Abstract

A: Detectors with a time resolution of a few tens of picoseconds and long-term durability in high particle fluxes are necessary for an accurate vertex separation in future particle physics experiments. The PICOSEC-Micromegas detector concept is a Micro-Pattern Gaseous Detector (MPGD) based solution addressing this particular challenge. It is based on a Micromegas detector coupled to a Cherenkov radiator and a photocathode. Primary electrons from the incident particles are generated in the photocathode and the time fluctuations due to different primary ionisation positions in the gaseous volume are reduced. The feasibility to reach a good time resolution using this concept was demonstrated in test beam studies, and time resolution values down to 24 ps were measured with muon beams at the CERN SPS accelerator complex. The previously simulated effects of different detector parameters on the time resolution were confirmed by measurements. For these measurements, a femtosecond laser system is used. For a single photoelectron, a time resolution of better than 50 ps is achieved mostly by minimising the drift gap distance. Furthermore, gain and Amplitude-to-Signal ratio (A/Q) with different gas mixtures are compared. K: Micropattern gaseous detectors (MSGC, GEM, THGEM, RETHGEM, MHSP, MI-CROPIC, MICROMEGAS, InGrid, etc); Particle tracking detectors (Gaseous detectors); Photon detectors for UV, visible and IR photons (gas) (gas-photocathodes, solid-photocathodes); Timing detectors

Precise timing and recent advancements with segmented anode PICOSEC Micromegas prototypes

“…It also reproduces the PICOSEC timing characteristics equally well as the detailed GARFIELD++ simulations. Driven by the phenomenological model, modified PICOSEC prototypes were designed and tested in laser beam at the IRAMIS facility at CEA-Saclay [4]. Using the aforementioned experimental setup, the PICOSEC was equipped with an Aluminium photocathode and the timing performance was studied with a fast photodiode (<3 ps) to serve as the time reference.…”

Current Status and Future Developments of Micromegas Detectors for Physics and Applications

“…An even higher increase of the drift field, with constant voltages, is achieved with reduced drift gaps down to 120 µm. With this configuration, a single photoelectron time resolution of 44 ± 1 ps is reached in the laser with a drift field of 44 kV/cm and an amplification field of 21 kV/cm [119]. This is an improvement of 32 ps compared to the single photoelectron time resolution of the first prototype of 76.0 ± 0.4 ps with 200 µm drift distance, a drift field of 21 kV/cm and an amplification field of 35 kV/cm [118].…”

Timing techniques with picosecond-order accuracy for novel gaseous detectors

“…The PICOSEC Micromegas detector has the potential for precise timing at the picosecond level [1,2]. In this work we develop a simulation model to train Artificial Neural Networks (ANN) for precise timing of PICOSEC [3] signals.…”

“…The aim is a fast online signal processing, as well as the minimisation of the necessary information to be saved during data acquisition. Two sets of PICOSEC waveforms were collected and digitized by a fast oscilloscope (20 GS/s) during a femtosecond-laser test beam run, with the PICOSEC operating at stable conditions [2]. In both sets a fast photodiode was used to time the laser pulses, with <3 ps resolution, and to provide an accurate time-reference for each PICOSEC digitized waveform.…”