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arXiv · 2301.00903

Magnetic Reconnection as the Driver of the Solar Wind

Nour E. Raouafi·G. Stenborg·D. B. Seaton·H. Wang·J. Wang·C. E. DeForest·S. D. Bale·J. F. Drake·V. M. Uritsky·J. T. Karpen·C. R. DeVore·A. C. Sterling·T. S. Horbury·L. K. Harra·S. Bourouaine·J. C. Kasper·P. Kumar·T. D. Phan·M. Velli
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Abstract

We present EUV solar observations showing evidence for omnipresent jetting activity driven by small-scale magnetic reconnection at the base of the solar corona. We argue that the physical mechanism that heats and drives the solar wind at its source is ubiquitous magnetic reconnection in the form of small-scale jetting activity (i.e., a.k.a. jetlets). This jetting activity, like the solar wind and the heating of the coronal plasma, are ubiquitous regardless of the solar cycle phase. Each event arises from small-scale reconnection of opposite polarity magnetic fields producing a short-lived jet of hot plasma and Alfv\'en waves into the corona. The discrete nature of these jetlet events leads to intermittent outflows from the corona, which homogenize as they propagate away from the Sun and form the solar wind. This discovery establishes the importance of small-scale magnetic reconnection in solar and stellar atmospheres in understanding ubiquitous phenomena such as coronal heating and solar wind acceleration. Based on previous analyses linking the switchbacks to the magnetic network, we also argue that these new observations might provide the link between the magnetic activity at the base of the corona and the switchback solar wind phenomenon. These new observations need to be put in the bigger picture of the role of magnetic reconnection and the diverse form of jetting in the solar atmosphere.

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Nour E. Raouafi, G. Stenborg, D. B. Seaton, H. Wang, J. Wang, C. E. DeForest, S. D. Bale, J. F. Drake, V. M. Uritsky, J. T. Karpen, C. R. DeVore, A. C. Sterling, T. S. Horbury, L. K. Harra, S. Bourouaine, J. C. Kasper, P. Kumar, T. D. Phan, M. Velli. 2023-01-03. Magnetic Reconnection as the Driver of the Solar Wind. https://doi.org/10.3847/1538-4357/acaf6c

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