Ultra-high-resolution observations of persistent null-point reconnection in the solar corona
Abstract
Magnetic reconnection is a key mechanism involved in solar eruptions and is also a prime possibility to heat the low corona to millions of degrees. 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.
Citation
Cheng , X , Priest , E R , Li , H T , Chen , J , Aulanier , G , Chitta , L P , Wang , Y L , Peter , H , Zhu , X S , Xing , C , Ding , M D , Solanki , S K , Berghmans , D , Teriaca , L , Aznar Cuadrado , R , Zhukov , A N , Guo , Y , Long , D , Harra , L , Smith , P J , Rodriguez , L , Verbeeck , C , Barczynski , K & Parenti , S 2023 , ' Ultra-high-resolution observations of persistent null-point reconnection in the solar corona ' , Nature Communications , vol. 14 , 2107 . https://doi.org/10.1038/s41467-023-37888-w
Publication
Nature Communications
Status
Peer reviewed
ISSN
2041-1723Type
Journal article
Rights
Copyright © The Author(s) 2023. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.
Description
Funding: X.C., H.L., J.C., Y.L.W., M.D.D., Y.G., and W.T.F. are funded by NSFC grants 11722325, 11733003, 11790303, and 11790300, and by the National Key R&D Program of China under grant 2021YFA1600504. X.C. is also supported by the Alexander von Humboldt foundation. L.P.C. gratefully acknowledges funding from the European Union. G.A. acknowledges financial support from the French national space agency (CNES), as well as from the Programme National Soleil Terre (PNST) of the CNRS/INSU also co-funded by CNES and CEA. X.S. acknowledges financial support by National Key R&D Program of China (2021YFA1600503), NSFC grant 11790301, and the mobility program (M-0068) of the Sino-German Science Center. A.N.Z. thanks to the Belgian Federal Science Policy Office (BELSPO) for the provision of financial support in the framework of the PRODEX Programme of the European Space Agency (ESA) under contract number 4000136424. D.M.L. is grateful to the Science Technology and Facilities Council for the award of an Ernest Rutherford Fellowship (ST/R003246/1).Collections
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