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arXiv · 2408.01591

MHD waves in homogeneous and continuously stratified atmospheres

Paul S. Cally·Thomas J. Bogdan
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Abstract

The basic equations, concepts, and modes of linear, ideal, MHD waves -- slow, Alfv\'en and fast -- are set out and generalised to gravitationally-stratified atmospheres. Particular attention is devoted to mode conversion, wherein the local behavior of a global wave changes from one mode to another in passing through particular atmospheric layers. Exact solutions are explored where available. Eikonal methods -- WKBJ and ray theory -- are described. Although our emphasis is on the theoretical underpinning of the subject, the solar atmospheric heating implications of fast/slow and fast/Alfv\'en conversions are discussed in detail.

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Paul S. Cally, Thomas J. Bogdan. 2024-08-02. MHD waves in homogeneous and continuously stratified atmospheres. https://doi.org/10.1016/b978-0-32-395664-2.00009-8

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