Single Particle Detection System for Strong-Field QED Experiments

TL;DR

This paper presents a novel single-particle detection system combining scintillation and Cherenkov detectors, designed to identify leptons from strong-field QED interactions amidst high background noise, validated through simulations and calibration.

Contribution

The paper introduces a new detector system capable of diagnosing single leptons in SF-QED experiments, with detailed performance analysis and background simulation results.

Findings

Expected detection of ~537 photons from 3 GeV leptons per calorimeter channel

Achieved a signal-to-noise ratio of 18 in the Cherenkov detector

Spectral resolution of 2% using pixelated LYSO screens

Abstract

Measuring signatures of strong-field quantum electrodynamics (SF-QED) processes in an intense laser field is an experimental challenge: it requires detectors to be highly sensitive to single electrons and positrons in the presence of the typically very strong x-ray and $\gamma$-photon background levels. In this paper, we describe a particle detector capable of diagnosing single leptons from SF-QED interactions and discuss the background level simulations for the upcoming Experiment-320 at FACET-II (SLAC National Accelerator Laboratory). The single particle detection system described here combines pixelated scintillation LYSO screens and a Cherenkov calorimeter. We detail the performance of the system using simulations and a calibration of the Cherenkov detector at the ELBE accelerator. Single 3 GeV leptons are expected to produce approximately 537 detectable photons in a single calorimeter channel. This signal is compared to Monte-Carlo simulations of the experiment. A signal-to-noise ratio of 18 in a single Cherenkov calorimeter detector is expected and a spectral resolution of 2% is achieved using the pixelated LYSO screens.