2001/01/15 by A. Meli, Meli, A., J. J. Quenby +1
Physics and Astronomy · #Astrophysics (astro-ph) #Astrophysics and Cosmic Phenomena #FOS: Physical sciences #Gamma-ray bursts and supernovae #Solar and Space Plasma Dynamics #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0101245
8 pages, 8 postscript figures, results presented in the 17th ECRS Lodz, Poland (2000)
openalex publication_date 2001/01/15 · arxiv created 2001/01/23 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In this paper we present an investigation of numerical Monte Carlo simulations of the diffusive shock acceleration in the test particle limit. Very high gamma flow astrophysical plasmas, have been used, from γup ∼50 up to γup ∼1000, which could be relevant to the suggested models of AGNs Jets and their Central Engines as well as the ultra-relativistic shock particle acceleration in Gamma Ray Burst (GRB) fireballs. Particularly the energy gain per shock crossing and the time constant for the above high relativistic processes is numerically calculated. We explicitly find a considerable γ2 energy boosting in the first shock cycle, and in all subsequent shock cycles the particle energy is multiplied by a large factor. Also a noted acceleration speed-up for the same acceleration process has been observed. Both of those results are connected with theoretical suggestions that a significant enhancement of the acceleration process is possible due to relativistic effects not present at lower plasma flow speeds. The acceleration speed-up and the mean energy-gain per shock cycle found could efficiently justify the theory of the origin of Ultra High Energy Cosmic Rays (UHECR) from the sites of GRBs.