Issue
EPL
Volume 85, Number 2, January 2009
Article Number 25001
Number of page(s) 5
Section Physics of Gases, Plasmas and Electric Discharges
DOI http://dx.doi.org/10.1209/0295-5075/85/25001
Published online 21 January 2009
EPL, 85 (2009) 25001
DOI: 10.1209/0295-5075/85/25001

Hall magnetohydrodynamics near an X-type magnetic neutral line

B. K. Shivamoggi

Los Alamos National Laboratory - Los Alamos, NM 87545, USA


received 26 August 2008; accepted in final form 10 December 2008; published January 2009
published online 21 January 2009

Abstract
Hall magnetohydrodynamics (MHD) near a two-dimensional (2D) X-type magnetic neutral line is considered. The Hall effects are shown to be able to sustain the hyperbolicity of the magnetic field (and hence a more open X-point configuration) near the neutral line in the steady state. This result is predicated on considering the steady Hall MHD state as the temporal asymptotic limit of the corresponding time-dependent problem. For the time-dependent Hall MHD problem, the Hall effects are shown to have a negligible impact on the current-sheet formation process near the X-type magnetic neutral line at short times but, subsequently, to quench the finite-time singularity exhibited in ideal MHD and, hence to prevent the plasma collapse, in consistency with the sustenance of the hyperbolicity of the magnetic field in the corresponding steady problem.

PACS
52.35.Vd - Magnetic reconnection.

© EPLA 2009