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Title: Electron-scale dynamics of the diffusion region during symmetric magnetic reconnection in space
Magnetic reconnection is an energy conversion process that occurs in many astrophysical contexts including Earth’s magnetosphere, where the process can be investigated in situ by spacecraft. On 11 July 2017, the four Magnetospheric Multiscale spacecraft encountered a reconnection site in Earth’s magnetotail, where reconnection involves symmetric inflow conditions. The electron-scale plasma measurements revealed (i) super-Alfvénic electron jets reaching 15,000 kilometers per second; (ii) electron meandering motion and acceleration by the electric field, producing multiple crescent-shaped structures in the velocity distributions; and (iii) the spatial dimensions of the electron diffusion region with an aspect ratio of 0.1 to 0.2, consistent with fast reconnection. The well-structured multiple layers of electron populations indicate that the dominant electron dynamics are mostly laminar, despite the presence of turbulence near the reconnection site.
Authors:
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Award ID(s):
1805829
Publication Date:
NSF-PAR ID:
10097836
Journal Name:
Science
Volume:
362
Issue:
6421
Page Range or eLocation-ID:
1391 to 1395
ISSN:
0036-8075
Sponsoring Org:
National Science Foundation
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