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arXiv · 2311.00456

Partial Eruption of Solar Filaments. I. Configuration and Formation of Double-decker Filaments

Abstract

Partial eruptions of solar filaments are the typical representative of solar eruptive behavior diversity. Here we investigate a typical filament partial eruption event and present integrated evidence for configuration of the pre-eruption filament and its formation. The CHASE H$\alpha$ observations reveal structured Doppler velocity distribution within the pre-eruption filament, where distinct redshift only appeared in the east narrow part of the south filament region and then disappeared after the partial eruption while the north part dominated by blueshift remained. Combining the SDO, ASO-S observations, and NLFFF modeling results, we verify that there were two independent material flow systems within the pre-flare filament, whose magnetic topology is a special double-decker configuration consisting of two magnetic flux ropes (MFRs) with opposite magnetic twist. During the formation of this filament system, continuous magnetic flux cancellation and footpoint motion were observed around its north end. Therefore, we propose a new double-decker formation scenario that the two MFRs composing such double-decker configuration originated from two magnetic systems with different initial connections and opposite magnetic twist. Subsequent magnetic reconnection with surrounding newly-emerging fields resulted in the motion of footpoint of the upper MFR to the region around footpoint of the lower MFR, thus leading to eventual formation of the double-decker configuration consisting of two MFRs with similar footpoints but opposite signs of magnetic twist. These results provide a potential way to determine unambiguously the progenitor configuration of a partial-eruptive filament and reveal a special type of double-decker MFR configuration and a new double-decker formation scenario.

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Yijun Hou, Chuan Li, Ting Li, Jiangtao Su, Ye Qiu, Shuhong Yang, Liheng Yang, Leping Li, Yilin Guo, Zhengyong Hou, Qiao Song, Xianyong Bai, Guiping Zhou, Mingde Ding, Weiqun Gan, Yuanyong Deng. 2023-11-01. Partial Eruption of Solar Filaments. I. Configuration and Formation of Double-decker Filaments. https://arxiv.org/abs/2311.00456

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