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| Titel |
Magnetic Local Time dependency in modeling of the Earth radiation belts |
| VerfasserIn |
Damien Herrera, Vincent Maget, Sebastien Bourdarie, Guy Rolland |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250141835
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| Publikation (Nr.) |
 EGU/EGU2017-5383.pdf |
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| Zusammenfassung |
| For many years, ONERA has been at the forefront of the modeling of the Earth radiation belts
thanks to the Salammbô model, which accurately reproduces their dynamics over a time scale
of the particles’ drift period. This implies that we implicitly assume an homogeneous
repartition of the trapped particles along a given drift shell. However, radiation belts are
inhomogeneous in Magnetic Local Time (MLT). So, we need to take this new coordinate
into account to model rigorously the dynamical structures, particularly induced
during a geomagnetic storm. For this purpose, we are working on both the numerical
resolution of the Fokker-Planck diffusion equation included in the model and on the
MLT dependency of physic-based processes acting in the Earth radiation belts. The
aim of this talk is first to present the 4D-equation used and the different steps we
used to build Salammbô 4D model before focusing on physical processes taken
into account in the Salammbô code, specially transport due to convection electric
field.
Firstly, we will briefly introduce the Salammbô 4D code developped by talking about its
numerical scheme and physic-based processes modeled. Then, we will focus our
attention on the impact of the outer boundary condition (localisation and spectrum) at
lower L∗ shell by comparing modeling performed with geosynchronous data from
LANL-GEO satellites. Finally, we will discuss the prime importance of the convection
electric field to the radial and drift transport of low energy particles around the Earth. |
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