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EP: Fachverband Extraterrestrische Physik
EP 7: Poster Session Extraterrestrics
EP 7.2: Poster
Dienstag, 31. März 2009, 17:30–19:00, Foyer der Zahnklinik
Ion Upwelling Associated with Ionospheric Heating — •Michael Danielides1, Mike Kosch2, and Michael Rietveld3 — 1IABG mbH, Einsteinstrasse 20, 85521 Ottobrunn, Germany — 2Lancaster University, Lancaster, LA1 4WA, UK — 3EISCAT Scientific Association, Ramfjordmoen, 9027 Ramfjordbotn, Norway
The mechanism for ion outflow from the auroral ionosphere into the magnetosphere is one of the fundamental open problems of space physics. It is widely accepted that this process is a multi-step process. In the first step ionospheric and thermospheric mechanisms provide an upwelling of oxygen and other heavy ions to higher than usual altitudes. These ions then constitute the seed population for the active acceleration mechanisms such as localized electric fields or inertial forces. Both of these steps are currently not understood.
The aim of the present study is an investigation and qualification of possible mechanisms which cause the ion upwelling. At first the ion upwelling is identified as a response to artificial ionospheric heating. Then a comparison of by incoherent scatter radar observed ion upflow characteristics (upward velocity, particle flux, temporal evolution) with numerical modeling of the heating and upward acceleration processes is performed. For this purpose we use data collected within the framework of an UK EISCAT high frequency ionospheric heating campaign from September til December 2007 at the EISCAT facility in Norway. The simulations are based on an advanced two-dimensional three fluid MHD model for small scale thermospheric and ionspheric processes.