Propagation characteristics of auroral kilometric radiation observed by the MEMO experiment on Interball 2

Abstract : The MEMO experiment is a part of the Interball 2 wave consortium. It is connected to a total of six electric and nine magnetic independent sensors. It provides waveforms associated with the measurement of two to five components in the thr• frequency bands: ELF (5-1000 Hz), VLF (1-20 kHz), and LF (20-250 kHz). Waveforms of thr• magnetic components and one electric component recorded during observations of auroral kilometric radiation (AKR) allow a detailed study of the characteristics of these emissions. In particular, the wave normal directions of AKR relative to the Earth's magnetic field are determined using several methods: the classical methods based on the plane wave approximation [Means, 1972] and the wave distribution function method which represents the evaluation of the wave energy density distribution with respect to the angular frequency and the wave normal direction(s). One event is fully analyzed in this paper. It is shown that AKR propagates with a polarization quasi-circular (ellipticity value-0.9), a right polarization (i.e., R-X mode), and wave normals weakly oblique (-300).