www.ann-geophys.net/19/1471/2001/ doi:10.5194/angeo-19-1471-2001 © European Geosciences Union 2001 Multi-spacecraft observations of broadband waves near the lower hybrid frequency at the Earthward edge of the magnetopause 1Swedish Institute of Space Physics, Uppsala division, Sweden 2University of Calgary, Canada 3CETP, Vélizy, France 4DESPA/CNRS, Observatoire de Paris, Meudon, France 5The Blackett Laboratory, Imperial College, London, UK 6Royal Institute of Technology, Stockholm, Sweden 7Space Science Laboratory, University of California at Berkeley, Berkeley, USA 8Department of Physics, University of Oslo, Norway 9Mullard Space Science Laboratory, University College London, London, UK Abstract. Broadband waves around the lower hybrid frequency (around 10 Hz) near the magnetopause are studied, using the four Cluster satellites. These waves are common at the Earthward edge of the boundary layer, consistent with earlier observations, and can have amplitudes at least up to 5 mV/m. These waves are similar on all four Cluster satellites, i.e. they are likely to be distributed over large areas of the boundary. The strongest electric fields occur during a few seconds, i.e. over distances of a few hundred km in the frame of the moving magnetopause, a scale length comparable to the ion gyroradius. The strongest magnetic oscillations in the same frequency range are typically found in the boundary layer, and across the magnetopause. During an event studied in detail, the magnetopause velocity is consistent with a large-scale depression wave, i.e. an inward bulge of magnetosheath plasma, moving tailward along the nominal magnetopause boundary. Preliminary investigations indicate that a rather flat front side of the large-scale wave is associated with a rather static small-scale electric field, while a more turbulent backside of the large-scale wave is associated with small-scale time varying electric field wave packets. Key words. Magnetospheric physics (magnetopause, cusp, and boundary layers) – Space plasma physics (waves and in-stabilities) Full Article (PDF, 2761 KB) Citation: André, M., Behlke, R., Wahlund, J.-E., Vaivads, A., Eriksson, A.-I., Tjulin, A., Carozzi, T. D., Cully, C., Gustafsson, G., Sundkvist, D., Khotyaintsev, Y., Cornilleau-Wehrlin, N., Rezeau, L., Maksimovic, M., Lucek, E., Balogh, A., Dunlop, M., Lindqvist, P.-A., Mozer, F., Pedersen, A., and Fazakerley, A.: Multi-spacecraft observations of broadband waves near the lower hybrid frequency at the Earthward edge of the magnetopause, Ann. Geophys., 19, 1471-1481, doi:10.5194/angeo-19-1471-2001, 2001. Bibtex EndNote Reference Manager XML |
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