 |
| Titel |
3D reconstruction and modelling of N2+ and OI auroral emissions using the Auroral Large Imaging System (ALIS) |
| VerfasserIn |
Cyril Simon Wedlund, Hervé Lamy, Bjorn Gustavsson, Tima Sergienko, Ingrid Sandahl, Urban Brändström |
| Konferenz |
EGU General Assembly 2011
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 13 (2011) |
| Datensatznummer |
250053476
|
|
|
|
|
|
| Zusammenfassung |
| In 2008 and 2009, coordinated campaigns between the European Incoherent Scatter Radar
(EISCAT) and the Auroral Large Imaging System (ALIS) situated in Northern Scandinavia
took place to study discrete auroral arcs.
With ALIS the N2+ (4278Å) band, the oxygen lines OI (5577Å) and OI (6300Å) can be
observed and their profiles can be reconstructed in 3D by means of tomography-like
reconstruction techniques. Inversions of the 3D reconstructed volume emission rate of N2+
and of the electron densities measured by EISCAT yield energy spectra of the precipitating
auroral electrons that can be used as input into transport kinetic/fluid models such as
TRANS4.
Both inversions give matching results with a typical average precipitation energy of a few
keV. The spatial and temporal extent of the auroral arcs is assessed using average arc width in
different wavelengths and the distribution of the characteristic electron energy as
parameters.
Comparisons between model and observations are presented for emission brightnesses
and electron densities, with predictions on the ion composition, ion chemistry and
backscattered fluxes. |
|
|
|
|
|
|