EDP Sciences
Free access
Volume 433, Number 3, April III 2005
Page(s) 1139 - 1143
Section The Sun
DOI http://dx.doi.org/10.1051/0004-6361:20041933

A&A 433, 1139-1143 (2005)
DOI: 10.1051/0004-6361:20041933

Viscous effects in planar magnetic X-point reconnection

I. J. D. Craig1, Y. E. Litvinenko2 and T. Senanayake1

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 )

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.

Key words: magnetohydrodynamics (MHD) -- Sun: flares

© ESO 2005