HR: 15:30h
AN: SP44A-01    [Abstracts]
TI: Roll Effect in Prominence Eruption Explained by Anisotropic Electrical Conductivity
AU: * Choe, G S
EM: gchoe@pppl.gov
AF: Princeton Plasma Physics Laboratory, P. O. Box 451, Princeton, NJ 08543 United States
AU: Cheng, C Z
EM: fcheng@pppl.gov
AF: Princeton Plasma Physics Laboratory, P. O. Box 451, Princeton, NJ 08543 United States
AU: Martin, S F
EM: sara@helioresearch.org
AF: Helio Research, 5212 Maryland Avenue, La Crescenta, CA 91214 United States
AB: When a prominence erupts, it generally rises non-radially and the top part of the prominence ribbon bends in one direction to make the ribbon horizontally flat. Also the legs of the prominence undergo twisting motions of opposite senses. This phenomenon was discovered and named as "role effect" by S. F. Martin. This effect can hardly be understood in the framework of ideal MHD or MHD with isotropic conductivity. Such breaking of a geometrical symmetry in the evolution of an initially symmetric system can take place when the electrical conductivity is anisotropic. We perform simulations of a solar plasma evolution with anisotropic electrical conductivity. Now the magnetic field does not only move together with plasma bulk flows, but also against electric currents. Thus the rising motion of the field is skewed to one direction. When magnetic reconnection takes place in a magnetic loop or arcade, the direction of the current in the current sheet region and in the region connected to this current sheet by field lines is opposite to that in the underlying reconnected loops. This explains why the Doppler shift at the top and outer parts of the erupting prominence is opposite to that in the bottom part between the prominence legs. Furthermore, this reasoning can account for how the sign of the roll effect depends on the chirality of the prominence as observed.
DE: 7524 Magnetic fields
DE: 7531 Prominence eruptions
DE: 7835 Magnetic reconnection
DE: 7843 Numerical simulation studies
SC: Solar Physics Division - AAS [SP]
MN: 2005 Joint Assembly