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arXiv · 2406.06368

Characteristics and Energy Flux Distributions of Decayless Transverse Oscillations Depending on Coronal Regions

Daye Lim·Tom Van Doorsselaere·David Berghmans·Elena Petrova
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Abstract

Lim et al. (2023) have recently proposed that the slope ($\delta$) of the power law distribution between the energy flux and oscillation frequency could determine whether high-frequency transverse oscillations give a dominant contribution to the heating ($\delta<1$). A meta-analysis of decayless transverse oscillations revealed that high-frequency oscillations potentially play a key role in heating the solar corona. We aim to investigate how (whether) the distributions of the energy flux contained in transverse oscillations, and their slopes, depend on the coronal region in which the oscillation occurs. We analyse transverse oscillations from 41 quiet Sun (QS) loops and 22 active region (AR) loops observed by Solar Orbiter/Extreme Ultraviolet Imager (SolO/EUI) HRIEUV. The energy flux and energy are estimated using analysed oscillation parameters and loop properties, such as periods, displacement amplitudes, loop lengths, and minor radii of the loops. It is found that about 71% of QS loops and 86% of AR loops show decayless oscillations. We find that the amplitude does not change depending on different regions, but the difference in the period is more pronounced. Although the power law slope ($\delta=-1.79$) in AR is steeper than that ($\delta=-1.59$) in QS, both of them are significantly less than the critical slope of 1. Our statistical study demonstrates that high-frequency transverse oscillations can heat the QS. For ARs, the total energy flux is insufficient unless yet-unobserved oscillations with frequencies up to 0.17 Hz are present. Future EUI campaigns will be planned to confirm this.

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Daye Lim, Tom Van Doorsselaere, David Berghmans, Elena Petrova. 2024-06-10. Characteristics and Energy Flux Distributions of Decayless Transverse Oscillations Depending on Coronal Regions. https://doi.org/10.1051/0004-6361/202450433

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