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arXiv · 2401.02123

Simultaneous observations of a breakout current sheet and a flare current sheet in a coronal jet event

Liheng Yang·Xiaoli Yan·Zhike Xue·Zhe Xu·Qingmin Zhang·Yijun Hou·Jincheng Wang·Huadong Chen
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Abstract

Previous studies have revealed that solar coronal jets triggered by the eruption of mini-filaments (MFs) conform to the famous magnetic-breakout mechanism. In such scenario, a breakout current sheet (BCS) and a flare current sheet (FCS) should be observed during the jets. With high spatial and temporal resolution data from the SDO, the NVST, the RHESSI, the Wind, and the GOES, we present observational evidence of a BCS and a FCS formation during coronal jets driven by a MF eruption occurring in the active region NOAA 11726 on 2013 April 21. Magnetic field extrapolation show that the MF was enclosed by a fan-spine magnetic structure. The MF was activated by flux cancellation under it, and then slowly rose. A BCS formed when the magnetic fields wrapping the MF squeezed to antidirectional external open fields. Simultaneously, one thin bright jet and two bidirectional jet-like structures were observed. As the MF erupted as a blowout jet, a FCS was formed when the two distended legs inside the MF field came together. One end of the FCS connected the post-flare loops. The peak temperature of BCS was calculated to be 2.5 MK. The length, width and peak temperature of FCS was calculated to be 4.35-4.93 Mm, 1.31-1.45 Mm, and 2.5 MK, respectively. The magnetic reconnection rate associated with the FCS was estimated to be from 0.266 to 0.333. This event also related to a type III radio burst, indicating its influence on interplanetary space. These observations support the scenario of the breakout model as the trigger mechanism of coronal jets, and flux cancellation was the driver of this event.

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Liheng Yang, Xiaoli Yan, Zhike Xue, Zhe Xu, Qingmin Zhang, Yijun Hou, Jincheng Wang, Huadong Chen. 2024-01-04. Simultaneous observations of a breakout current sheet and a flare current sheet in a coronal jet event. https://arxiv.org/abs/2401.02123

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