ResearchVideos

Ultra-high-resolution observations of persistent null-point reconnection in the solar corona

6 107 2024/04/14

Authors:

Research Videos ( author1@researchvideos.net )

Abstract :

Here, we present ultra-high-resolution extreme ultraviolet observations of persistent null-point reconnection in the corona at a scale of about 390 km over one hour observations of the Extreme-Ultraviolet Imager on board Solar Orbiter spacecraft. The observations show formation of a null-point conﬁguration above a minor positive polarity embedded within a region of dominant negative polarity near a sunspot. The gentle phase of the persistent null-point reconnection is evidenced by sustained point-like high-temperature plasma (about 10 MK) near the null-point and constant outﬂow blobs not only along the outer spine but also along the fan surface. The blobs appear at a higher frequency than previously observed with an average velocity of about 80 km s−1 and life-times of about 40 s. The null-point reconnection also occurs explosively but only for 4 minutes, its coupling with a mini-ﬁlament eruption generates a spiral jet. These results suggest that magnetic reconnection, at previously unresolved scales, proceeds continually in a gentle and/or explosive way to persistently transfer mass and energy to the overlying corona.

Keywords :

["solar eruptions","magnetic reconnection","Extreme-Ultraviolet Imager","high-temperature plasma","spiral jet"]

Disciplines :

Physics

Subdisciplines :

Astronomy , Astrophysics , Plasma Physics

Video Type :

Publishing Licence :

Open-access

Submitted On :

2024/04/14

References :

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