|
Titel |
Density and temperature of energetic electrons in the Earth's magnetotail derived from high-latitude GPS observations during the declining phase of the solar cycle |
VerfasserIn |
M. H. Denton, T. E. Cayton |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
0992-7689
|
Digitales Dokument |
URL |
Erschienen |
In: Annales Geophysicae ; 29, no. 10 ; Nr. 29, no. 10 (2011-10-07), S.1755-1763 |
Datensatznummer |
250017103
|
Publikation (Nr.) |
copernicus.org/angeo-29-1755-2011.pdf |
|
|
|
Zusammenfassung |
Single relativistic-Maxwellian fits are made to high-latitude GPS-satellite
observations of energetic electrons for the period January 2006–November 2010; a
constellation of 12 GPS space vehicles provides the observations. The
derived fit parameters (for energies ~0.1–1.0 MeV), in combination
with field-line mapping on the nightside of the magnetosphere, provide a
survey of the energetic electron density and temperature distribution in the
magnetotail between McIlwain L-values of L=6 and L=22. Analysis reveals the
characteristics of the density-temperature distribution of energetic
electrons and its variation as a function of solar wind speed and the Kp
index. The density-temperature characteristics of the magnetotail energetic
electrons are very similar to those found in the outer electron radiation
belt as measured at geosynchronous orbit. The energetic electron density in
the magnetotail is much greater during increased geomagnetic activity and
during fast solar wind. The total electron density in the magnetotail is
found to be strongly correlated with solar wind speed and is at least a
factor of two greater for high-speed solar wind (VSW=500–1000 km s−1)
compared to low-speed solar wind (VSW=100–400 km s−1).
These results have important implications for understanding (a) how the
solar wind may modulate entry into the magnetosphere during fast and slow
solar wind, and (b) if the magnetotail is a source or a sink for the outer
electron radiation belt. |
|
|
Teil von |
|
|
|
|
|