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arXiv · 0806.2406

Magneto-thermal condensation modes including the effects of charged dust particles

Mohsen Shadmehri·Sami Dib
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Abstract

We study thermal instability in a magnetized and partially ionized plasma with charged dust particles. Our linear analysis shows that the growth rate of the unstable modes in the presence of dust particles strongly depends on the ratio of the cooling rate and the modified dust-cyclotron frequency. If the cooling rate is less than the modified dust-cyclotron frequency, then growth rate of the condensation modes does not modify due to the existence of the charged dust particles. But when the cooling rate is greater than (or comparable to) the modified dust-cyclotron frequency, the growth rate of unstable modes increases because of the dust particles. Also, wavenumber of the perturbations corresponding to the maximum growth rate shifts to the smaller values (larger wavelengths) as the cooling rate becomes larger than the modified dust-cyclotron frequency. We show that growth rate of the condensation modes increases with the electrical charge of the dust particles.

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Mohsen Shadmehri, Sami Dib. 2009-02-03. Magneto-thermal condensation modes including the effects of charged dust particles. https://doi.org/10.1111/j.1365-2966.2009.14589.x

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