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arXiv · 2106.16227

Diagnostic Techniques for Particle-in-Cell Simulations of Laser-produced Gamma-rays in the Strong-field QED Regime

A. H. Younis·A. Davidson·B. Hafizi·D. F. Gordon
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Abstract

The emission of multi-MeV ($\gamma$-ray) photons from the interaction of a high-powered laser pulse with a dense plasma target is studied using particle-in-cell simulations. A new set of diagnostic techniques is presented and applied to analyze the intense field and ultra-relativistic electrons. Such methods elucidate the dominant processes responsible for efficient laser-to-$\gamma$ energy conversion, which include nonlinear Compton scattering and magneto-bremsstrahlung radiation, and provide a clear picture of the interaction on a microscopic level. We identify regions in the plasma target of high photon energy-density and obtain an energy conversion efficiency as high as 30%. The essential characteristics of the interaction are validated with full-3D simulations.

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A. H. Younis, A. Davidson, B. Hafizi, D. F. Gordon. 2021-06-30. Diagnostic Techniques for Particle-in-Cell Simulations of Laser-produced Gamma-rays in the Strong-field QED Regime. https://arxiv.org/abs/2106.16227

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