Expansion of solar corona in the Sun's gravitational field and formation of the heliospheric current sheet

Abstract

[1]  Taking into account gravitation and the temperature gradient, three-dimensional MHD simulation of solar corona expansion in a dipole magnetic field was performed. Dissipation, compressibility, and anisotropy of thermal conductivity were taken into consideration. For calculations, the PERESVET code was used. It was been shown that a heliospheric current sheet having a normal component of magnetic field is formed. An important result is that the establishment of the stationary plasma outflow has been found to be extremely sensitive to the corona plasma parameters. For typical corona parameters, the flow becomes supersonic at a distance of more than three solar radii.

Received 24 May 2004; revised 22 March 2005; accepted 3 May 2005; published 18 October 2005.

Keywords: Solar corona; Heliospheric current sheet; Supersonic plasma outflow.

Index Terms: 7509 Solar Physics, Astrophysics, and Astronomy: Corona; 7827 Space Plasma Physics: Kinetic and MHD theory; 7524 Solar Physics, Astrophysics, and Astronomy: Magnetic fields.