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arXiv · 0704.2828

Are "EIT Waves" Fast-Mode MHD Waves?

M. J. Wills-Davey·C. E. DeForest·J. O. Stenflo
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Abstract

We examine the nature of large-scale, coronal, propagating wave fronts (``EIT waves'') and find they are incongruous with solutions using fast-mode MHD plane-wave theory. Specifically, we consider the following properties: non-dispersive single pulse manifestions, observed velocities below the local Alfven speed, and different pulses which travel at any number of constant velocities, rather than at the ``predicted'' fast-mode speed. We discuss the possibility of a soliton-like explanation for these phenomena, and show how it is consistent with the above-mentioned aspects.

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M. J. Wills-Davey, C. E. DeForest, J. O. Stenflo. 2007-04-23. Are "EIT Waves" Fast-Mode MHD Waves?. https://doi.org/10.1086/519013

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