Simulations of laser-plasma experiments at the QED frontier

Lasers at the forefront of laser-matter interaction research are rapidly advancing, and computer simulations need to keep pace. Experiments are reaching intensity regimes where new physics---quantum electrodynamics (QED) corrections to otherwise classical plasma dynamics, specifically radiation reaction---becomes important. In an effort to validate models before they are widely deployed in experimental and application design, we run QED-particle-in-cell simulations of short-pulse laser-plasma experiments with parameters that are achievable today. We describe a novel process of self-formation of a channel in an unstructured target that enhances the laser fields and results in a characteristic dipole pattern of high-energy photon emission. The self-formation process is robust to experimentally motivated variations in our simulations, and present in simulations using historical shot data from the Texas Petawatt. We investigate shot-to-shot variations in simulations, how a new observable can be used to diagnose experiments and aid in detection of QED photons, and related challenges in simulating experiments.