Magnetic Field and Radiation Production in Laser-Driven Electron Beams
John Peterson, Stanford University
Relativistic charged-particle beams are routinely produced in the most extreme environments in the universe, from gamma-ray bursts in distant galaxies to intense lasers and electron beam facilities on Earth. As these beams interact with a background plasma, they can generate strong magnetic fields that accelerate particles to high energies and emit bright electromagnetic radiation. In the first part of the talk we present results from the OMEGA-EP laser of a picosecond laser-driven magnetic vortex. The lower plasma density and longer beam than in previous magnetic vortex studies enables us to characterize the fields for the first time using proton radiography. Validating the theoretical model behind these fields represents an important step to high-energy ion acceleration with magnetic vortices. In the second part of the talk, we use kinetic plasma theory and simulations to show that laboratory-scale electron beams with the proper shape and charge can excite plasma instabilities thought to power gamma-ray bursts. We derive experimental requirements and address common obstacles to diagnose and harness these plasma instabilities to generate bright, high-energy X-rays in the laboratory. Simulations indicate that electron beams from modern femtosecond laser wakefield accelerators can generate large fluxes of 100s-keV photons urgently needed for high energy density science experiments.
Authors: J. Ryan Peterson1,2,3, Nuno Lemos2, Siegfried Glenzer3, Frederico Fiuza3
1Stanford University, United States2Lawrence Livermore National Laboratory, United States
3SLAC National Accelerator Laboratory, United States
Abstract Author(s): (see above entries)