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| Titel |
The ionospheric signature of transient dayside reconnection and the associated pulsed convection return flow |
| VerfasserIn |
S. E. Milan, Mark Lester, R. A. Greenwald, G. Sofko |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
0992-7689
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| Digitales Dokument |
URL |
| Erschienen |
In: Annales Geophysicae ; 17, no. 9 ; Nr. 17, no. 9, S.1166-1171 |
| Datensatznummer |
250013809
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| Publikation (Nr.) |
 copernicus.org/angeo-17-1166-1999.pdf |
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| Zusammenfassung |
Three SuperDARN coherent HF radars are
employed to investigate the excitation of convection in the dayside
high-latitude ionosphere in response to transient reconnection occurring in the
cusp region. This study demonstrates the existence of transient
antisunward-propagating backscatter features at the expected location of the
ionospheric footprint of the cusp region, which have a repetition rate near 10
min. These are interpreted as the ionospheric signature of flux transfer events.
Moreover, transient sunward-propagating regions of backscatter are observed in
the convection return flow regions of both the pre- and post-noon sectors. These
patches are observed to propagate towards the noon sector from at least as far
around the auroral zone as 07 MLT in the pre-noon sector and 17 MLT in the
post-noon sector, travelling with a velocity of approximately 1.5 to 2 km s-1.
These return flow patches have a repetition rate similar to that of the
transient features observed at local noon. While providing supporting evidence
for the impulsive nature of convection flow, the observation of
sunward-propagating features in the return flow region is not consistent with
current conceptual models of the excitation of convection.
Key words. Ionosphere (plasma convection) ·
Magnetospheric physics (magnetopause · cusp · and boundary layers;
magnetosphere-ionosphere interactions) |
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