Single particle detection system for strong-field QED experiments
F. C. Salgado, N. Cavanagh, Matteo Tamburini, D. Storey, R. Beyer, P. H. Bucksbaum, Z. Chen, A. Di Piazza, E. Gerstmayr, Harsh Harsh, E Isele, A. Junghans, Christoph H. Keitel, Stephan Kuschel, Christian F. Nielsen, David A. Reis, Christian Roedel, G. Sarri, Andreas Seidel, Christian Schneider, E. Uggerhøj, Jörg Wulff, V. Yakimenko, Carola Zepter, Sebastian Meuren, M. Zepf
Abstract
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 γ -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.