Two-dimensional hybrid models of ion dynamics in collisionless quasi-perpendicular shocks Academic Article uri icon

abstract

  • Spacecraft observations show that collisionless shocks are ubiquitous in the heliosphere from CME shock fronts to the heliospheric termination shock with broad range of Mach numbers. Evidently, quasi-perpendicular collisionless shocks undergo structural changes with the increase of the Mach number. These changes are related to the increasing role of the reflected ions, which have a highly non-gyrotropic distribution. Eventually, it is expected that the shock front becomes non-stationary and rippled. At low and moderate Mach numbers the fraction of reflected ions is small, yet recent observations show existence of a well-pronounced structure of the post-shock magnetic field in the close vicinity of the transition layer. Here we show, using 2D hybrid simulations, that the gyration of the directly transmitted ions downstream of the ramp produces spatial pressure variations …

publication date

  • December 1, 2012