Description
With today’s accelerator and laser facilities, such as the 10 GeV FACET-II facility at SLAC National Accelerator Laboratory or laser-accelerated electron beams at multipetawatt laser facilities, extreme beam physics is emerging as a promising science area where ultrashort and dense electron beams can be used as a source of TV/m fields, enabling high field matter interaction and new applications in photon science and particle acceleration. In this talk I will present an overview of recent experimental progress, prospects and physics opportunities for the FACET-II accelerator facility and the multipetawatt laser facilities APOLLON and ELI-NP. By delivering extreme electron beams with peak current reaching 100 kA, corresponding to petawatt peak power at 10 GeV, these facilities enable a broad science program ranging from high-field plasma-based acceleration, laboratory astrophysics, extreme focusing and attosecond sources, and probing quantum electrodynamics at the scale of the Schwinger critical field in the so-called strong-field quantum electrodynamics (SFQED) regime. I will highlight recent breakthroughs achieved at FACET-II, such as the most precise measurements of quantum radiation reaction to date, the generation of 100-kA class beams by laser-electron beam shaping, the demonstration of a brightness and energy transformer, efficient plasma acceleration with percent-level field uniformity, and extreme beam focusing by leveraging intense coherent transition radiation in beam-multifoil collisions. At laser facilities, I will show that extreme beam focusing is also possible thanks to the high current of the laser-accelerated electron beams, and I will highlight how plasma mirrors can be used to generate self-aligned nonlinear inverse Compton scattering from high-energy electron beams, opening the way to the study of SFQED at fields well above the Schwinger critical field.