Viscous effects in planar magnetic X-point reconnection

¹ Department of Mathematics, University of Waikato, Private Bag 3105, Hamilton, New Zealand e-mail: sts1@math.waikato.ac.nz
² Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, NH 03824, USA

Received: 1 September 2004
Accepted: 15 December 2004

Abstract

The impact of viscous dissipation is considered on magnetic reconnection in closed line-tied magnetic X-points. It is shown that viscous effects can provide fast energy dissipation for disturbances which do not alter the initial X-point topology. If the X-point topology is altered, then the rate of viscous dissipation depends on both the perturbed topology and the relative magnitudes of viscosity and electric resistivity. New solutions are demonstrated, which derive from the combination of resistive and viscous effects. The solutions are characterized by monotonically decaying modes which are qualitatively different from the previously known oscillatory modes in nonviscous resistive X-point reconnection. These results suggest that viscous heating in magnetic X-points may be an important effect in solar flares.