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arXiv · 2501.02753

A Scenario for Origin of Global 4 mHz Oscillations in Solar Corona

Li Xue·Cheng-Liang Jiao·Li-Xin Zhang
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Abstract

We establish a spherically symmetric model of solar atmosphere, which consists of the whole chromosphere and low corona below the $1.25$ solar radius. It is a hydrodynamic model with heating in the chromosphere through an artificial energy flux. We performed a series of simulations with our model and found oscillations with a peak frequency of $\sim$4 $\rm{mHz}$ in the power spectrum. We confirmed that this resulted from the $p$-mode excited in the transition region and amplified in a resonant cavity situated in the height range $\sim$$4\times10^3$--$2\times10^4$ km. This result is consistent with global observations of Alfv\'enic waves in corona and can naturally explain the observational ubiquity of $4\ \rm{mHz}$ without the difficulty of the $p$-mode passing through the acoustic-damping chromosphere. We also confirmed that acoustic shock waves alone cannot heat the corona to the observed temperature, and found mass upflows in the height range $\sim$$7\times10^3$--$7\times10^4$ km in our model, which pumped the dense and cool plasma into the corona and might be the mass supplier for solar prominences.

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Li Xue, Cheng-Liang Jiao, Li-Xin Zhang. 2025-01-06. A Scenario for Origin of Global 4 mHz Oscillations in Solar Corona. https://doi.org/10.3390/universe11010014

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