HR: 0800h
AN: SM51C-0379    [Abstracts]
TI: Alfven Vortex Filament-Like Structures Observed by Cluster Downstream the Bow-Shock
AU: * Mangeney, A
EM: mangeney@despace.obspm.fr
AF: Observatoire de Paris, 5 place Jules Janssen, Meudon, 92195 France
AU: Alexandrova, O
EM: olga.alexandrova@obspm.fr
AF: Observatoire de Paris, 5 place Jules Janssen, Meudon, 92195 France
AU: Maksimovic, M
EM: milan.maksimovic@obspm.fr
AF: Observatoire de Paris, 5 place Jules Janssen, Meudon, 92195 France
AU: Cornilleau, N
EM: nicole.cornilleau@cetp.ipsl.fr
AF: CETP, 10-12, av. de l'Europe, Velizy, 78140 France
AU: Lucek, E
EM: e.lucek@imperial.ac.uk
AF: Imperial College, Prince Consort Road, London, SW7 2BZ United Kingdom
AU: Bosqued, J
EM: jean-michel.bosqued@cesr.fr
AF: CESR, 9, av. du Colonel Roche, Toulouse, 31028 France
AU: Andr\'e, M
EM: Mats.Andre@irfu.se
AF: Swedish Institute of Space Physics, Uppsala Division Box 537 , Uppsala, SE-751 21 Sweden
AB: In the downstream region of the perpendicular bow-shock, localised coherent magnetic structures are observed. Using the four Cluster satellites we show that the structures are localized in time and space and that they are transported by the plasma flow. We identify these structures as field-aligned cylindrical currents almost in magnetostatic equilibrium but with a vortical structure, Alfv\'en vortex filaments. Analysing a set of such Alfv\'en filaments we find that they are distributed quasi-periodically in the plane perpendicular to an average magnetic field. Investigating several shock crossings, we show that the characteristic scale of a filament depends on the distance to the shock front.
DE: 7851 Shock waves
DE: 2724 Magnetopause, cusp, and boundary layers
DE: 2728 Magnetosheath
DE: 2752 MHD waves and instabilities
DE: 2772 Plasma waves and instabilities
SC: SPA-Magnetospheric Physics [SM]
MN: 2004 AGU Fall Meeting