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arXiv · 2502.16579

Quasiperiodic Super-Alfvenic Slippage Along Flare Ribbons Observed by the Interface Region Imaging Spectrograph

Yining Zhang·Ting Li·Yijun Hou·Xuchun Duan·Zheng Sun·Guiping Zhou
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Abstract

The apparent slipping motion of flare loops is regarded as a key feature of the 3D magnetic reconnection in the solar flares. The slippage with a super-Alfv\'enic speed could be defined as slipping-running reconnection while the slippage with a sub-Alfv\'enic speed is called slipping reconnection. Due to the limitation of the observational instrument temporal resolution, the apparent slippage of the flare loop footpoints along the flare ribbons with super-Alfv\'enic speed is quite rare to our knowledge. In this paper, we report a unique event that exhibits not only the sub-Alfv\'enic slippage, but also the quasiperiodic super-Alfv\'enic slippage of ribbon substructures during a C3.4-class flare (SOL2023-01-18-T15:23), using the high temporal resolution observations of the Interface Region Imaging Spectrograph ($\sim$2 s). The super-Alfv\'enic slippage with a speed of up to $\sim$ 1688 km s$^{-1}$ is directly observed in this study. The calculated period of the apparent super-Alfv\'enic slippage in both ribbons is between 8.4 and 11.9 seconds. This work provides the first observational evidence of the periodicity for the slipping-running magnetic reconnection.

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Yining Zhang, Ting Li, Yijun Hou, Xuchun Duan, Zheng Sun, Guiping Zhou. 2025-02-23. Quasiperiodic Super-Alfvenic Slippage Along Flare Ribbons Observed by the Interface Region Imaging Spectrograph. https://arxiv.org/abs/2502.16579

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