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arXiv · 2112.11756

Possible Signature of Sausage Waves in Photospheric Bright Points

Yuhang Gao·Fuyu Li·Bo Li·Wenda Cao·Yongliang Song·Hui Tian·Mingzhe Guo
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Abstract

Sausage waves have been frequently reported in solar magnetic structures such as sunspots, pores, and coronal loops. However, they have not been unambiguously identified in photospheric bright points (BPs). Using high-resolution TiO image sequences obtained with the Goode Solar Telescope at the Big Bear Solar Observatory, we analyzed four isolated BPs. It was found that their area and average intensity oscillate for several cycles in an in-phase fashion. The oscillation periods range from 100 to 200 seconds. We interpreted the phase relation as a signature of sausage waves, particularly slow waves, after discussing sausage-wave theory and the opacity effect.

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Yuhang Gao, Fuyu Li, Bo Li, Wenda Cao, Yongliang Song, Hui Tian, Mingzhe Guo. 2021-12-22. Possible Signature of Sausage Waves in Photospheric Bright Points. https://doi.org/10.1007/s11207-021-01928-9

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