Structure of the current sheet in the 11 July 2017 Electron Diffusion Region Event
File(s)
Author(s)
Type
Journal Article
Abstract
The structure of the current sheet along the Magnetospheric Multiscale (MMS) orbit is examined during the 11 July 2017 Electron Diffusion Region (EDR) event. The location of MMS relative to the X‐line is deduced and used to obtain the spatial changes in the electron parameters. The electron velocity gradient values are used to estimate the reconnection electric field sustained by nongyrotropic pressure. It is shown that the observations are consistent with theoretical expectations for an inner EDR in 2‐D reconnection. That is, the magnetic field gradient scale, where the electric field due to electron nongyrotropic pressure dominates, is comparable to the gyroscale of the thermal electrons at the edge of the inner EDR. Our approximation of the MMS observations using a steady state, quasi‐2‐D, tailward retreating X‐line was valid only for about 1.4 s. This suggests that the inner EDR is localized; that is, electron outflow jet braking takes place within an ion inertia scale from the X‐line. The existence of multiple events or current sheet processes outside the EDR may play an important role in the geometry of reconnection in the near‐Earth magnetotail.
Date Issued
2019-02
Date Acceptance
2018-12-19
Citation
Journal of Geophysical Research: Space Physics, 2019, 124 (2), pp.1173-1186
ISSN
2169-9380
Publisher
American Geophysical Union (AGU)
Start Page
1173
End Page
1186
Journal / Book Title
Journal of Geophysical Research: Space Physics
Volume
124
Issue
2
Copyright Statement
© 2018 The Authors. This is an open access article under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Sponsor
Science and Technology Facilities Council (STFC)
Grant Number
ST/N000692/1
Publication Status
Published
Date Publish Online
2019-02-27