Work

An exact collisionless equilibrium for the Force-Free Harris Sheet with low plasma beta

Year: 2015

Type: article

Abstract: We present a first discussion and analysis of the physical properties of a new exact collisionless equilibrium for a one-dimensional nonlinear force-free magnetic field, namely, the force-free Harris sheet. The solution allows any value of the plasma beta, and crucially below unity, which previous nonlinear force-free collisionless equilibria could not. The distribution function involves infinite series of Hermite polynomials in the canonical momenta, of which the important mathematical properties of convergence and non-negativity have recently been proven. Plots of the distribution function are presented for the plasma beta modestly below unity, and we compare the shape of the distribution function in two of the velocity directions to a Maxwellian distribution.

Source: Physics of Plasmas

DOI: 10.1063/1.4934611

Authors: O. Allanson, T. Neukirch, F. Wilson, S. Troscheit

Institution: University of St Andrews

Language: English

Topic: Ionosphere and magnetosphere dynamics

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: hybrid

Funders: Leverhulme Trust, European Commission, Engineering and Physical Sciences Research Council, Science and Technology Facilities Council