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Temperature Anisotropy in a Shocked Plasma: Mirror-Mode Instabilities in the Heliosheath

Y. Liu·J. D. Richardson·J. W. Belcher·J. C. Kasper
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Abstract

We show that temperature anisotropies induced at a shock can account for interplanetary and planetary bow shock observations. Shocked plasma with enhanced plasma beta is preferentially unstable to the mirror mode instability downstream of a quasi-perpendicular shock and to the firehose instability downstream of a quasi-parallel shock, consistent with magnetic fluctuations observed downstream of a large variety of shocks. Our theoretical analysis of the solar wind termination shock suggests that the magnetic holes observed by Voyager 1 in the heliosheath are produced by the mirror mode instability. The results are also of astrophysical interest, providing an energy source for plasma heating.

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Y. Liu, J. D. Richardson, J. W. Belcher, J. C. Kasper. 2007-02-22. Temperature Anisotropy in a Shocked Plasma: Mirror-Mode Instabilities in the Heliosheath. https://doi.org/10.1086/516568

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