skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Relativistic, perpendicular shocks in electron-positron plasmas

Journal Article · · Astrophysical Journal; (United States)
DOI:https://doi.org/10.1086/171326· OSTI ID:7287708
; ; ; ;  [1]
  1. Lawrence Livermore National Laboratory, Livermore, CA (United States)

One-dimensional particle-in-cell plasma simulations are used to examine the mechanical structure and thermalization properties of collisionless relativistic shock waves in electron-positron plasmas. Shocks propagating perpendicularly to the magnetic field direction are considered. It is shown that these shock waves exist, and that they are completely parameterized by the ratio of the upstream Poynting flux to the upstream kinetic energy flux. The way in which the Rankine-Hugoniot shock jump conditions are modified by the presence of wave fluctuations is shown, and they are used to provide a macroscopic description of these collisionless shock flows. The results of a 2D simulation that demonstrates the generality of these results beyond the assumption of the 1D case are discussed. It is suggested that the thermalization mechanism is the formation of a synchrotron maser by the coherently reflected particles in the shock front. Because the downstream medium is thermalized, it is argued that perpendicular shocks in pure electron-positron plasmas are not candidates as nonthermal particle accelerators. 40 refs.

OSTI ID:
7287708
Journal Information:
Astrophysical Journal; (United States), Vol. 391:1; ISSN 0004-637X
Country of Publication:
United States
Language:
English