Simultaneous Double Star and Cluster FTEs observations on the dawnside flank of the magnetosphere
We present Cluster and Double Star-1 (TC-1) observations from a close magnetic conjunction on 8 May 2004. The five spacecraft were on the dawnside flank of the magnetosphere, with TC-1 located near the equatorial plane and Cluster at higher geographic latitudes in the Southern Hemisphere...
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Copernicus Publications
2005-11-01
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Series: | Annales Geophysicae |
Online Access: | https://www.ann-geophys.net/23/2877/2005/angeo-23-2877-2005.pdf |
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author | A. Marchaudon C. J. Owen J.-M. Bosqued R. C. Fear A. N. Fazakerley M. W. Dunlop A. D. Lahiff C. Carr A. Balogh P.-A. Lindqvist H. Rème |
author_facet | A. Marchaudon C. J. Owen J.-M. Bosqued R. C. Fear A. N. Fazakerley M. W. Dunlop A. D. Lahiff C. Carr A. Balogh P.-A. Lindqvist H. Rème |
author_sort | A. Marchaudon |
collection | DOAJ |
description | We present Cluster and Double Star-1 (TC-1) observations from a close
magnetic conjunction on 8 May 2004. The five spacecraft were on the
dawnside flank of the magnetosphere, with TC-1 located near the equatorial
plane and Cluster at higher geographic latitudes in the Southern Hemisphere.
TC-1, at its apogee, skimmed the magnetopause for almost 8h (between
08:00-16:00 UT). Flux Transfer Events (FTEs), moving southward/tailward from
the reconnection site, were observed by TC-1 throughout almost all of the
period. Cluster, travelling on a mainly dawn-dusk trajectory, crossed the
magnetopause at around 10:30 UT in the same Magnetic Local Time (MLT) sector
as TC-1 and remained close to the magnetopause boundary layer in the
Southern Hemisphere. The four Cluster spacecraft observed FTEs for a period
of 6.5h between 07:30 and 14:00 UT.
<P style="line-height: 20px;">
The very clear signatures and the finite transverse sizes of the FTEs
observed by TC-1 and Cluster imply that, during this event, sporadic
reconnection occurred. From the properties of these FTEs, the reconnection
site was located northward of both TC-1 and Cluster on the dawn flank of the
magnetosphere. Reconnection occurred between draped magnetosheath and closed
magnetospheric field lines. Despite variable interplanetary magnetic field
(IMF) conditions and IMF-<i>B<sub>z</sub></i> turnings, the IMF clock angle remained
greater than 70° and the location site appeared to remain relatively
stable in position during the whole period. This result is in agreement with
previous studies which reported that the dayside reconnection remained
active for an IMF clock angle greater than 70°. The simultaneous
observation of FTEs at both Cluster and TC-1, separated by 2h in MLT,
implies that the reconnection site on the magnetopause must have been
extended over several hours in MLT. |
first_indexed | 2024-12-22T12:48:09Z |
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issn | 0992-7689 1432-0576 |
language | English |
last_indexed | 2024-12-22T12:48:09Z |
publishDate | 2005-11-01 |
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series | Annales Geophysicae |
spelling | doaj.art-cc3ab2086fe84200a457f506938435642022-12-21T18:25:17ZengCopernicus PublicationsAnnales Geophysicae0992-76891432-05762005-11-01232877288710.5194/angeo-23-2877-2005Simultaneous Double Star and Cluster FTEs observations on the dawnside flank of the magnetosphereA. Marchaudon0C. J. Owen1J.-M. Bosqued2R. C. Fear3A. N. Fazakerley4M. W. Dunlop5A. D. Lahiff6C. Carr7A. Balogh8P.-A. Lindqvist9H. Rème10Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, RH5 6NT, UKMullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, RH5 6NT, UKCentre d’Etude Spatiale des Rayonnements, CESR/CNRS, B.P. 4346, 31028 Toulouse Cedex, FranceMullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, RH5 6NT, UKMullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, RH5 6NT, UKRutherford-Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX, UKMullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, RH5 6NT, UKSpace and Atmospheric Physics, Blackett Laboratory, Imperial College, London, SW7 2BZ, UKSpace and Atmospheric Physics, Blackett Laboratory, Imperial College, London, SW7 2BZ, UKAlfvén Laboratory, Royal Institute of Technology, Stockholm, 10044, SwedenCentre d’Etude Spatiale des Rayonnements, CESR/CNRS, B.P. 4346, 31028 Toulouse Cedex, FranceWe present Cluster and Double Star-1 (TC-1) observations from a close magnetic conjunction on 8 May 2004. The five spacecraft were on the dawnside flank of the magnetosphere, with TC-1 located near the equatorial plane and Cluster at higher geographic latitudes in the Southern Hemisphere. TC-1, at its apogee, skimmed the magnetopause for almost 8h (between 08:00-16:00 UT). Flux Transfer Events (FTEs), moving southward/tailward from the reconnection site, were observed by TC-1 throughout almost all of the period. Cluster, travelling on a mainly dawn-dusk trajectory, crossed the magnetopause at around 10:30 UT in the same Magnetic Local Time (MLT) sector as TC-1 and remained close to the magnetopause boundary layer in the Southern Hemisphere. The four Cluster spacecraft observed FTEs for a period of 6.5h between 07:30 and 14:00 UT. <P style="line-height: 20px;"> The very clear signatures and the finite transverse sizes of the FTEs observed by TC-1 and Cluster imply that, during this event, sporadic reconnection occurred. From the properties of these FTEs, the reconnection site was located northward of both TC-1 and Cluster on the dawn flank of the magnetosphere. Reconnection occurred between draped magnetosheath and closed magnetospheric field lines. Despite variable interplanetary magnetic field (IMF) conditions and IMF-<i>B<sub>z</sub></i> turnings, the IMF clock angle remained greater than 70° and the location site appeared to remain relatively stable in position during the whole period. This result is in agreement with previous studies which reported that the dayside reconnection remained active for an IMF clock angle greater than 70°. The simultaneous observation of FTEs at both Cluster and TC-1, separated by 2h in MLT, implies that the reconnection site on the magnetopause must have been extended over several hours in MLT.https://www.ann-geophys.net/23/2877/2005/angeo-23-2877-2005.pdf |
spellingShingle | A. Marchaudon C. J. Owen J.-M. Bosqued R. C. Fear A. N. Fazakerley M. W. Dunlop A. D. Lahiff C. Carr A. Balogh P.-A. Lindqvist H. Rème Simultaneous Double Star and Cluster FTEs observations on the dawnside flank of the magnetosphere Annales Geophysicae |
title | Simultaneous Double Star and Cluster FTEs observations on the dawnside flank of the magnetosphere |
title_full | Simultaneous Double Star and Cluster FTEs observations on the dawnside flank of the magnetosphere |
title_fullStr | Simultaneous Double Star and Cluster FTEs observations on the dawnside flank of the magnetosphere |
title_full_unstemmed | Simultaneous Double Star and Cluster FTEs observations on the dawnside flank of the magnetosphere |
title_short | Simultaneous Double Star and Cluster FTEs observations on the dawnside flank of the magnetosphere |
title_sort | simultaneous double star and cluster ftes observations on the dawnside flank of the magnetosphere |
url | https://www.ann-geophys.net/23/2877/2005/angeo-23-2877-2005.pdf |
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