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

Abstract

Previous studies have revealed that solar coronal jets triggered by the eruption of minifilaments (MFs) conform to the famous magnetic-breakout mechanism. In such a 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 shows 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 BCS’s peak temperature was calculated to be 2.5 MK. The FCS’s length, width, and peak temperature were calculated to be 4.35–4.93, 1.31–1.45, 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 is 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.

On the Determining Physical Factor of Jet-related Coronal Mass Ejections’ Morphology in the High Corona

“…In a high-resolution MHD simulation, Wyper et al (2017Wyper et al ( , 2018 showed a breakout model (Antiochos et al 1999) for coronal jets in a 3D fan-spine structure involving small filaments. The instability and eruptions of the filament may be caused by the photospheric flux emergence and/or cancellation (e.g., Shen et al 2012a;Adams et al 2014;Panesar et al 2017;Chen et al 2018Chen et al , 2020Tang et al 2021), or breakout reconnection (e.g., Wyper et al 2017;Kumar et al 2018;Wyper et al 2018;Kumar et al 2019;Sun et al 2023;Yang et al 2024). The jets are produced by the latter process as the filament flux reconnects with and releases twists into the external magnetic flux.…”