Abstract
Abstract The full kinetic dynamics of a perpendicular collisionless shock is studied by means of a one-dimensional electromagnetic full particle simulation. The present simulation domain is taken in the shock rest frame in contrast to the previous full particle simulations of shocks. Preliminary results show that the downstream state falls into a unique cyclic reformation state for a given set of upstream parameters through the self-consistent kinetic processes.
Highlights
Collisionless shocks are universal processes in space and are observed in laboratory, astrophysical, and space plasmas, including astrophysical jets, an interstellar medium, the heliosphere, and the planetary magnetosphere
The magnetic piston method (Lembege and Dawson, 1987a; Lembege and Savoini, 1992) is widely used in full particle simulations, in which a plasma is accelerated by an external current pulse applied at one side of the simulation domain
The plasma is pushed by the “magnetic piston” into the background plasma, and the external pulse develops into a shock wave
Summary
Collisionless shocks are universal processes in space and are observed in laboratory, astrophysical, and space plasmas, including astrophysical jets, an interstellar medium, the heliosphere, and the planetary magnetosphere. The downstream region taken in the right-hand side of the simulation domain is prepared with the drift velocity ux, density n2, isotropic temperatures Te2 and Ti2, and magnetic field B0y2. In addition to the upstream quantities ux, ωpe, ωce, vte, and rT 1, we need the downstream ion-to-electron temperature ratio, rT 2, so as to uniquely determine the other downstream quantities ux, ωpe, ωce, and vte from the shock jump conditions for a magnetized two-fluid plasma consisting of electrons and ions with the equal bulk velocity and the equal number density. Since we performed the present simulation on a personal computer, we used a reduced ion-to-electron mass ratio rm = 100 for computational efficiency With these parameters, we obtain the initial downstream quantities as ωpe2 = 1.95, ωce2 = −0.19, ux2 = 1.05, and vte2 = 7.55. The numerical noises due to random motions of individual particles are substantially reduced by adopting second-order schemes (Umeda, 2004)
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call