Signatures of magnetic separatrices at the borders of a crater flux transfer event connected to an active X‐line

File Description SizeFormat 
Trenchi_JGR_2019_submission4_accepted.pdfAccepted version1.83 MBAdobe PDFView/Open
Title: Signatures of magnetic separatrices at the borders of a crater flux transfer event connected to an active X‐line
Authors: Trenchi, L
Coxon, JC
Fear, RC
Eastwood, JP
Dunlop, MW
Trattner, KJ
Gershman, DJ
Graham, DB
Khotyaintsev, Y
Lavraud, B
Item Type: Journal Article
Abstract: In this paper, we present Magnetospheric Multiscale (MMS) observations of a flux transfer event (FTE) characterized by a clear signature in the magnetic field magnitude, which shows maximum at the center flanked by two depressions, detected during a period of stable southward interplanetary magnetic field. This class of FTEs are called “crater‐FTEs” and have been suggested to be connected with active reconnection X line. The MMS burst mode data allow the identification of intense fluctuations in the components of the electric field and electron velocity parallel to the magnetic field at the borders of the FTE, which are interpreted as signatures of the magnetic separatrices. In particular, the strong and persistent fluctuations of the parallel electron velocity at the borders of this crater‐FTE reported for the first time in this paper, sustain the field‐aligned current part of the Hall current system along the separatrix layer, and confirm that this FTE is connected with an active reconnection X line. Our observations suggest a stratification of particles inside the reconnection layer, where electrons are flowing toward the X line along the separatrix, are flowing away from the X line along the reconnected field lines adjacent to the separatrices, and more internally ions and electrons are flowing away from the X line with comparable velocities, forming the reconnection jets. This stratification of the reconnection layer forming the FTE, together with the reconnection jet at the trailing edge of the FTE, suggests clearly that this FTE is formed by the single X line generation mechanism.
Issue Date: 9-Nov-2019
Date of Acceptance: 27-Sep-2019
URI: http://hdl.handle.net/10044/1/74703
DOI: 10.1029/2018ja026126
ISSN: 2169-9380
Publisher: American Geophysical Union (AGU)
Journal / Book Title: Journal of Geophysical Research: Space Physics
Copyright Statement: ©2019. American Geophysical Union. All Rights Reserved. This is the accepted version of the following article: Trenchi, L., Coxon, J. C., Fear, R. C., Eastwood, J. P., Dunlop, M. W., Trattner, K. J., et al ( 2019). Signatures of magnetic separatrices at the borders of a crater flux transfer event connected to an active X‐line. Journal of Geophysical Research: Space Physics, 124, which has been published in final form at https://doi.org/10.1029/2018JA026126
Sponsor/Funder: Science and Technology Facilities Council (STFC)
Funder's Grant Number: ST/N000692/1
Publication Status: Published online
Article Number: 2018JA026126
Online Publication Date: 2019-10-17
Appears in Collections:Space and Atmospheric Physics
Physics



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

Creative Commons