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K. E. Korreck (University of Michgan- Ann Arbor)
Collisionless shocks play a role in many astrophysical phenomena, from coronal mass ejections (CMEs) in the heliosphere to supernova remnants. In these shocks, plasma waves transfer heat, kinetic energy, and momentum. The degree of post-shock thermal equilibrium of the shocked region determines the number of high speed electrons available for injection into an acceleration process that could produce cosmic rays. CMEs form collisionless shock fronts as they propagate through the heliosphere, heating heavy ions preferentially [Berdichevsky et al. (1997)]. This is in contrast to the supernova data which shows less than mass proportional heating. In this talk we will examine ion heating in CME events and supernova. We used the ACE satellite to examine the CME events and the FUSE satellite for UV spectral data from SN1006. We find that the heliospheric CME data confirms the greater than mass proportional heating while the SN1006 data is approximately mass proportional. To understand the differences at the collisionless shock front, a Monte Carlo model simulated neutral particles as they pass through the shock. Neutrals could create a precursor to the shock additionally heating the plasma causing a preferential heating. Using this model and the two data sets, a model was formed to examine the plasma waves, such as lower hybrid waves, involved in heating and their effect on the shock characteristics in the two different systems. These waves have varying effects on the species in the plasma based on the mass and charge of the species. The SN1006 work was supported by NASA grant NEG5-10352 to the Smithsonian Astrophysical Observatory. K.E. Korreck was supported by the University of Michigan Rackham-NSF Engineering Award.
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Bulletin of the American Astronomical Society, 36 5
© 2004. The American Astronomical Society.