A new hybrid code (CHIEF) implementing the inertial electron fluid equation without approximation
Abstract
We present a new hybrid algorithm implemented in the code CHIEF (Code Hybrid with Inertial Electron Fluid) for simulations of electronion plasmas. The algorithm treats the ions kinetically, modeled by the ParticleinCell (PiC) method, and electrons as an inertial fluid, modeled by electron fluid equations without any of the approximations used in most of the other hybrid codes with an inertial electron fluid. This kind of code is appropriate to model a large variety of quasineutral plasma phenomena where the electron inertia and/or ion kinetic effects are relevant. We present here the governing equations of the model, how these are discretized and implemented numerically, as well as six test problems to validate our numerical approach. Our chosen test problems, where the electron inertia and ion kinetic effects play the essential role, are: 0) Excitation of parallel eigenmodes to check numerical convergence and stability, 1) parallel (to a background magnetic field) propagating electromagnetic waves, 2) perpendicular propagating electrostatic waves (ion Bernstein modes), 3) ion beam righthand instability (resonant and nonresonant), 4) ion Landau damping, 5) ion firehose instability, and 6) 2D oblique ion firehose instability. Our results reproduce successfully the predictions of linear and nonlinear theory for all these problems, validating our code. All properties of this hybrid code make it ideal to study multiscale phenomena between electron and ion scales such as collisionless shocks, magnetic reconnection and kinetic plasma turbulence in the dissipation range above the electron scales.
 Publication:

Computer Physics Communications
 Pub Date:
 March 2018
 DOI:
 10.1016/j.cpc.2017.10.012
 arXiv:
 arXiv:1612.03818
 Bibcode:
 2018CoPhC.224..245M
 Keywords:

 Plasma simulation;
 Hybrid methods;
 Particleincell method;
 Physics  Plasma Physics;
 Physics  Computational Physics
 EPrint:
 57 pages, 19 figures. Revised to match with the version published in Computer Physics Communications