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arXiv · 2405.04766

Multiwavelength observations of a breakout jet at an active region periphery

Pradeep Kayshap·Judith T. Karpen·Pankaj Kumar
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Abstract

We analysed Interface-Region Imaging Spectrograph (IRIS) and the Solar Dynamics Observatory/Atmospheric Imaging Assembly (SDO/AIA) observations of a small coronal jet that occurred at the solar west limb on 2014 August 29. The jet source region, a small bright point, was located at an active-region periphery and contains a fan-spine topology with a mini-filament. Our analysis has identified key features and timings that motivate the following interpretation of this event. As the stressed core flux rises, a current sheet forms beneath it; the ensuing reconnection forms a flux rope above a flare arcade. When the rising filament-carrying flux rope reaches the stressed null, it triggers a jet via explosive interchange (breakout) reconnection. During the flux-rope interaction with the external magnetic field, we observed brightening above the filament and within the dome, along with a growing flare arcade. EUV images reveal quasi-periodic ejections throughout the jet duration with a dominant period of 4 minutes, similar to coronal jetlets and larger jets. We conclude that these observations are consistent with the magnetic breakout model for coronal jets.

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Pradeep Kayshap, Judith T. Karpen, Pankaj Kumar. 2024-05-08. Multiwavelength observations of a breakout jet at an active region periphery. https://arxiv.org/abs/2405.04766

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