Cluster observations of a field aligned current at the dawn flank of a bursty bulk flow
This article describes observations of a bursty bulk flow (BBF) in the outer central plasma sheet. The observations are made with the Cluster satellites, located approximately 19 <I>R<sub>E</sub></I> downtail, close to the midnight sector in the Southern Hemisphere. 40&...
| Main Authors: | , , , , , , , , , , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2007-06-01
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| Series: | Annales Geophysicae |
| Online Access: | https://www.ann-geophys.net/25/1405/2007/angeo-25-1405-2007.pdf |
| _version_ | 1828832158146363392 |
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| author | K. Snekvik S. Haaland S. Haaland N. Østgaard H. Hasegawa R. Nakamura T. Takada T. Takada L. Juusola O. Amm F. Pitout H. Rème B. Klecker E. A. Lucek |
| author_facet | K. Snekvik S. Haaland S. Haaland N. Østgaard H. Hasegawa R. Nakamura T. Takada T. Takada L. Juusola O. Amm F. Pitout H. Rème B. Klecker E. A. Lucek |
| author_sort | K. Snekvik |
| collection | DOAJ |
| description | This article describes observations of a bursty bulk flow (BBF) in the outer
central plasma sheet. The observations are made with the Cluster satellites,
located approximately 19 <I>R<sub>E</sub></I> downtail, close to the midnight sector in the
Southern Hemisphere. 40–60 s after Cluster first detected the BBF, there
was a large bipolar perturbation in the magnetic field. A Grad-Shafranov
reconstruction has revealed that this is created by a field-aligned current
at the flank of the BBF. Further analysis of the plasma moments has shown
that the BBF has the properties of a depleted flux tube. Depleted flux tubes
are an important theoretical model for how plasma and magnetic flux can be
transported Earthward in the magnetotail as part of the Dungey cycle. The
field aligned current is directed Earthward and is located at the dawn side
of the BBF. Thus, it is consistent with the magnetic shear at the flank of an
Earthward moving BBF. The total current has been estimated to be about
0.1 MA. |
| first_indexed | 2024-12-12T16:48:12Z |
| format | Article |
| id | doaj.art-f6a9551d7dfe4ac282303cd4ef0c59b4 |
| institution | Directory Open Access Journal |
| issn | 0992-7689 1432-0576 |
| language | English |
| last_indexed | 2024-12-12T16:48:12Z |
| publishDate | 2007-06-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Annales Geophysicae |
| spelling | doaj.art-f6a9551d7dfe4ac282303cd4ef0c59b42022-12-22T00:18:26ZengCopernicus PublicationsAnnales Geophysicae0992-76891432-05762007-06-01251405141510.5194/angeo-25-1405-2007Cluster observations of a field aligned current at the dawn flank of a bursty bulk flowK. Snekvik0S. Haaland1S. Haaland2N. Østgaard3H. Hasegawa4R. Nakamura5T. Takada6T. Takada7L. Juusola8O. Amm9F. Pitout10H. Rème11B. Klecker12E. A. Lucek13Department of Physics and Technology, University of Bergen, Bergen, NorwayDepartment of Physics and Technology, University of Bergen, Bergen, NorwayMax-Planck-Institut für Extraterrestrische Physik, Garching, GermanyDepartment of Physics and Technology, University of Bergen, Bergen, NorwayInstitute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, JapanSpace Research Institute, Austrian Academy of Sciences, Graz, AustriaInstitute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, JapanSpace Research Institute, Austrian Academy of Sciences, Graz, AustriaFinnish Meteorological Institute, Space Research Unit, FinlandFinnish Meteorological Institute, Space Research Unit, FinlandMax-Planck-Institut für Extraterrestrische Physik, Garching, GermanyCentre d'Etude Spatiale des Rayonnements, Toulouse, FranceMax-Planck-Institut für Extraterrestrische Physik, Garching, GermanySpace and Atmospheric Physics, Imperial College, London, UKThis article describes observations of a bursty bulk flow (BBF) in the outer central plasma sheet. The observations are made with the Cluster satellites, located approximately 19 <I>R<sub>E</sub></I> downtail, close to the midnight sector in the Southern Hemisphere. 40–60 s after Cluster first detected the BBF, there was a large bipolar perturbation in the magnetic field. A Grad-Shafranov reconstruction has revealed that this is created by a field-aligned current at the flank of the BBF. Further analysis of the plasma moments has shown that the BBF has the properties of a depleted flux tube. Depleted flux tubes are an important theoretical model for how plasma and magnetic flux can be transported Earthward in the magnetotail as part of the Dungey cycle. The field aligned current is directed Earthward and is located at the dawn side of the BBF. Thus, it is consistent with the magnetic shear at the flank of an Earthward moving BBF. The total current has been estimated to be about 0.1 MA.https://www.ann-geophys.net/25/1405/2007/angeo-25-1405-2007.pdf |
| spellingShingle | K. Snekvik S. Haaland S. Haaland N. Østgaard H. Hasegawa R. Nakamura T. Takada T. Takada L. Juusola O. Amm F. Pitout H. Rème B. Klecker E. A. Lucek Cluster observations of a field aligned current at the dawn flank of a bursty bulk flow Annales Geophysicae |
| title | Cluster observations of a field aligned current at the dawn flank of a bursty bulk flow |
| title_full | Cluster observations of a field aligned current at the dawn flank of a bursty bulk flow |
| title_fullStr | Cluster observations of a field aligned current at the dawn flank of a bursty bulk flow |
| title_full_unstemmed | Cluster observations of a field aligned current at the dawn flank of a bursty bulk flow |
| title_short | Cluster observations of a field aligned current at the dawn flank of a bursty bulk flow |
| title_sort | cluster observations of a field aligned current at the dawn flank of a bursty bulk flow |
| url | https://www.ann-geophys.net/25/1405/2007/angeo-25-1405-2007.pdf |
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