MHD WAVES IN THE COLLISIONAL PLASMA OF THE SOLAR CORONA AND TERRESTRIAL IONOSPHERE

Journal Title: Solar-Terrestrial Physics - Year 2020, Vol 6, Issue 4

Abstract

We have studied MHD waves (Alfvén and fast compressional modes) in a homogeneous collisional three-component low-β plasma. The three-component plasma consists of electrons, ions, and neutrals with arbitrary ratio between collision frequencies and wave time scales. We have derived a general dispersion equation and relationships for phase velocity and collisional damping rates for MHD modes for various limiting cases: from weak collisions to a strong collisional coupling, and for longitudinal and oblique propagation. In a weak collision limit, the MHD eigen-modes are reduced to ordinary low-damping Alfvén and fast magnetosonic waves. For a partially ionized plasma with a strong collisional coupling of neutrals and ions, velocities of magnetosonic and Alfvén waves are substantially reduced, as compared to the Alfvén velocity in the ideal MHD theory. At a very low frequency, when neutrals and ions are strongly coupled, a possibility arises of weakly damping MHD modes, called “decelerated” MHD modes. These modes can be observed in the solar corona/chromosphere and in the F layer of the terrestrial ionosphere.

Authors and Affiliations

Nekrasov A. K. , Pilipenko V. A.

Keywords

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  • EP ID EP700238
  • DOI 10.12737/stp-64202003
  • Views 131
  • Downloads 0

How To Cite

Nekrasov A. K. , Pilipenko V. A. (2020). MHD WAVES IN THE COLLISIONAL PLASMA OF THE SOLAR CORONA AND TERRESTRIAL IONOSPHERE. Solar-Terrestrial Physics, 6(4), -. https://europub.co.uk/articles/-A-700238