Turbulent magneto-genesis in a collisionless plasma
Abstract
We investigate an efficient mechanism for generating magnetic fields in turbulent, collisionless plasmas. By using fully kinetic, particle-in-cell simulations of an initially non-magnetized plasma, we inspect the genesis of magnetization, in a nonlinear regime. The complex motion is initiated via a Taylor-Green vortex, and the plasma locally develops strong electron temperature anisotropy, due to the strain tensor of the turbulent flow. Subsequently, in a domino effect, the anisotropy triggers a Weibel instability, localized in space. In such active wave-particle interaction regions, the magnetic field seed grows exponentially and spreads to larger scales due to the interaction with the underlying stirring motion. Such a self-feeding process might explain magneto-genesis in a variety of astrophysical plasmas, wherever turbulence is present.
Keywords
Cite
@article{arxiv.2109.07432,
title = {Turbulent magneto-genesis in a collisionless plasma},
author = {F. Pucci and M. Viviani and F. Valentini and G. Lapenta and W. H. Matthaeus and S. Servidio},
journal= {arXiv preprint arXiv:2109.07432},
year = {2021}
}