Project Details
Towards pair production in the non-perturbative regime: Ultra-relativistic beams, laser characterisation and pair detection
Applicants
Professor Dr. Stefan Karsch; Professor Dr. Matt Zepf
Subject Area
Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
Term
since 2019
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 392856280
Creating pairs of matter and antimatter from pure energy in the form of massless photons is one of the fundamental processes in quantum electrodynamics (QED). Yet its experimental realisation in a photon-photon vacuum interaction in general nor specifically in the limit of a many-photon interaction (commonly termed non-perturbative regime) has still not been achieved. This involves colliding a multi-GeV $\gamma$~photon with around 40-80 infrared laser photons simultaneously, the latter supplied by an ultraintese laser pulse. This regime is of particular interest because it can test the validity of current theoretical models of non-perturbative QED. In the first funding period, through numerical simulations we have established a detailed model of the planned setup, its expected signal rate and signal-to-noise ratio, and key components have been designed and partially tested. In the next funding period we plan to push the energy of the primary electron beam that generates the gamma-beam over the 2.5 GeV barrier, by implementing new plasma targets and ramping up the drive laser energy, test the pair detectors' response with multi-GeV $\gamma$~beams at the Stanford Linear Accelerator Centre (SLAC) and perform the integrated pair production experiment at CALA in Garching.
DFG Programme
Research Units