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arXiv · 2607.25799

High-Frequency Magnetohydrodynamic Waves with Substantial Energy in the Solar Polar Corona

Yuhang Gao·Hui Tian·Richard Morton·Tom Van Doorsselaere·Daye Lim·Mingzhe Guo·Jiansen He·Zhenyong Hou
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Abstract

The acceleration and heating of the fast solar wind remain long-standing challenges in space physics. One type of leading theoretical models requires high-frequency magnetohydrodynamic (MHD) waves to transport and dissipate sufficient energy in the corona. However, such high-frequency waves with energetically significant amplitudes have never been unambiguously observed, leaving a key gap between theories and observations. Using high-cadence, high-resolution extreme-ultraviolet imaging from Solar Orbiter's Extreme Ultraviolet Imager, we identify a previously hidden population of high-frequency MHD waves in coronal plumes of the solar polar region. An analysis of the detected propagating kink waves shows that over one-third have periods shorter than 100 s, a population largely undetected by earlier instruments. Power spectral analysis demonstrates that these high-frequency waves carry substantial energy flux, which are significantly underestimated in lower-cadence data. These results suggest that high-frequency MHD waves may contribute importantly to the energy budget of the solar polar corona and could play a role in solar wind acceleration, highlighting the value of high-resolution observations for probing energy transport in magnetized space and astrophysical plasmas.

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Yuhang Gao, Hui Tian, Richard Morton, Tom Van Doorsselaere, Daye Lim, Mingzhe Guo, Jiansen He, Zhenyong Hou. 2026-07-28. High-Frequency Magnetohydrodynamic Waves with Substantial Energy in the Solar Polar Corona. https://doi.org/10.1093/nsr%2Fnwag370

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