2007/11/27 by Donald C. Ellison, Andrey Vladimirov
Physics and Astronomy · #Acceleration #Astrophysical Phenomena and Observations #Astrophysics and Cosmic Phenomena #Cosmic ray #Electron #Field (mathematics) #Magnetic field #Monte Carlo method #Particle acceleration #Plasma #Solar and Space Plasma Dynamics #Supernova #astro-ph
paper · pdf · doi:10.1086/527359
Submitted to ApJ Letters October 2007, 5 pages with 2 figures
arxiv created 2007/11/27 · openalex publication_date 2007/12/28 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Evidence is accumulating suggesting that collisionless shocks in supernova remnants (SNRs) can amplify the interstellar magnetic field to hundreds of microgauss or even milligauss levels, as recently claimed for SNR RX J1713.7–3946. If these fields exist, they are almost certainly created by magnetic field amplification (MFA) associated with the efficient production of cosmic rays by diffusive shock acceleration (DSA) and their existence strengthens the case for SNRs being the primary source of Galactic cosmic-ray ions to the "knee" and beyond. However, the high magnetic field values in SNRs are obtained exclusively from the interpretation of observations of radiation from relativistic electrons, and if MFA via nonlinear DSA produces these fields, the magnetic field that determines the maximum ion energy will be substantially less than the field that determines the maximum electron energy. We use results of a steady-state Monte Carlo simulation to show how nonlinear effects from efficient cosmic-ray production and MFA reduce the maximum energy of protons relative to what would be expected from test-particle acceleration.