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تسجيل مستخدم جديدElectron-Scale Dynamics of the Diffusion Region during Symmetric Magnetic Reconnection in Space
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Magnetic reconnection is an energy conversion process important in many astrophysical contexts including the Earths magnetosphere, where the process can be investigated in-situ. Here we present the first encounter of a reconnection site by NASAs Magnetospheric Multiscale (MMS) spacecraft in the magnetotail, where reconnection involves symmetric inflow conditions. The unprecedented electron-scale plasma measurements revealed (1) super-Alfvenic electron jets reaching 20,000 km/s, (2) electron meandering motion and acceleration by the electric field, producing multiple crescent-shaped structures, (3) spatial dimensions of the electron diffusion region implying a reconnection rate of 0.1-0.2. The well-structured multiple layers of electron populations indicate that, despite the presence of turbulence near the reconnection site, the key electron dynamics appears to be largely laminar.
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