Numerical study of Weibel instability driven by anisotropic electron temperature in collisionless plasmas

TL;DR

This study compares kinetic and hybrid models to understand magnetic field generation via Weibel instability driven by electron temperature anisotropy in collisionless plasmas, highlighting the effectiveness of hydrodynamical approaches for large-scale simulations.

Contribution

It provides a detailed comparison between fully kinetic and hybrid models, demonstrating the viability of simplified hydrodynamical methods for simulating Weibel instability.

Findings

Good agreement in magnetic field magnitude between models

Hydrodynamical approach can approximate kinetic results

Hybrid modeling is effective for large-scale plasma simulations

Abstract

We numerically investigate the process of generating magnetic fields from temperature anisotropy of electrons in collisionless initially uniform plasmas. We use a fully kinetic modeling and compare it against a hybrid modeling which treats ions kinetically and use ten-moment fluid model for electrons. The results of the one-to-one comparison show a good agreement in terms of the maximal magnitude of the self-generated magnetic field and similar trends during the non-linear stage of the instability. Additionally, we performed hybrid modelling of the instability without resolving electron spatial scales. In this case the results are only qualitatively the same however it shows that hydrodynamical approach can be used to some extent for the simulation of the Weibel instability in large-scale systems, including astrophysical environments and laser-produced plasmas.