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arXiv · 1007.1080

Observational evidence of resonantly damped propagating kink waves in the solar corona

G. Verth·M. Goossens·J. Terradas
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Abstract

In this Letter we establish clear evidence for the resonant absorption damping mechanism by analyzing observational data from the novel Coronal Multi-Channel Polarimeter (CoMP). This instrument has established that in the solar corona there are ubiquitous propagating low amplitude ($\approx$1 km s$^{-1}$) Alfvénic waves with a wide range of frequencies. Realistically interpreting these waves as the kink mode from magnetohydrodynamic (MHD) wave theory, they should exhibit a frequency dependent damping length due to resonant absorption, governed by the TGV relation showing that transversal plasma inhomogeneity in coronal magnetic flux tubes causes them to act as natural low-pass filters. It is found that observed frequency dependence on damping length (up to about 8 mHz) can be explained by the kink wave interpretation and furthermore, the spatially averaged equilibrium parameter describing the length scale of transverse plasma density inhomogeneity over a system of coronal loops is consistent with the range of values estimated from TRACE observations of standing kink modes.

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G. Verth, M. Goossens, J. Terradas. 2010-07-07. Observational evidence of resonantly damped propagating kink waves in the solar corona. https://doi.org/10.1088/2041-8205%2F718%2F2%2Fl102

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