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arXiv · 1911.11849

The Distinction Between Thermal Nonequilibrium and Thermal Instability

James A. Klimchuk
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Abstract

For some forms of steady heating, coronal loops are in a state of thermal nonequilibrium and evolve in a manner that includes accelerated cooling, often resulting in the formation of a cold condensation. This is frequently confused with thermal instability, but the two are in fact fundamentally different. We explain the distinction and discuss situations where they may be interconnected. Large-amplitude perturbations, perhaps associated with MHD waves, likely play a role in explaining phenomena that have been attributed to thermal nonequilibrium but also seem to require cross-field communication.

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James A. Klimchuk. 2019-11-26. The Distinction Between Thermal Nonequilibrium and Thermal Instability. https://doi.org/10.1007/s11207-019-1562-z

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