Charged particle timing at sub-25 picosecond precision: the PICOSEC detection concept

TL;DR

The PICOSEC detection concept achieves sub-25 picosecond timing resolution for charged particles using a two-stage Micromegas detector with various configurations tested in beam campaigns, showing promising results for future large-area applications.

Contribution

This work demonstrates the performance of the PICOSEC detector prototype with different configurations and discusses strategies for scaling up for future experiments.

Findings

Single-photoelectron response of 76 ps measured with femtosecond UV laser.

Time resolution of 24 ps achieved with 150 GeV muons.

Performance varies with readout and photocathode configurations.

Abstract

The PICOSEC detection concept consists in a "two-stage" Micromegas detector coupled to a Cherenkov radiator and equipped with a photocathode. A proof of concept has already been tested: a single-photoelectron response of 76 ps has been measured with a femtosecond UV laser at CEA/IRAMIS, while a time resolution of 24 ps with a mean yield of 10.4 photoelectrons has been measured for 150 GeV muons at the CERN SPS H4 secondary line. This work will present the main results of this prototype and the performance of the different detector configurations tested in 2016-18 beam campaigns: readouts (bulk, resistive, multipad) and photocathodes (metallic+CsI, pure metallic, diamond). Finally, the prospects for building a demonstrator based on PICOSEC detection concept for future experiments will be discussed. In particular, the scaling strategies for a large area coverage with a multichannel readout plane, the R\&D on solid converters for building a robust photocathode and the different resistive configurations for a robust readout.