2009/03/31 by S. F. Martins, R. A. Fonseca, L. O. Silva +1 · 1 citation
Physics and Astronomy · #Astrophysics and Cosmic Phenomena #Laser-Plasma Interactions and Diagnostics #Solar and Space Plasma Dynamics #astro-ph.HE #physics.plasm-ph
paper · pdf · doi:10.1088/0004-637x/695/2/l189
published as Astrophys.J.695:L189-L193,2009 · 5 pages, 3 figures
arxiv created 2009/04/03 · openalex publication_date 2009/04/03 · arxiv updated 2011/02/11 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
Ab initio numerical study of collisionless shocks in electron–ion unmagnetized plasmas is performed with fully relativistic particle in cell simulations. The main properties of the shock are shown, focusing on the implications for particle acceleration. Results from previous works with a distinct numerical framework are recovered, including the shock structure and the overall acceleration features. Particle tracking is then used to analyze in detail the particle dynamics and the acceleration process. We observe an energy growth in time that can be reproduced by a Fermi-like mechanism with a reduced number of scatterings, in which the time between collisions increases as the particle gains energy, and the average acceleration efficiency is not ideal. The in depth analysis of the underlying physics is relevant to understanding the generation of high-energy cosmic rays, the impact on the astrophysical shock dynamics, and the consequent emission of radiation.