04/16/02
LE-CONTEL OLIVIER Centre d'etude des Environnements Terrestre et Planetaires (CETP)
10-12, AVENUE DE L"EUROPE SF2A- PNPS- PNP- PNST-
78140 VELIZY, FRANCE
Presentation 1 : Oral
Rapid changes of the magnetic field topology in the magnetotail: theory and CLUSTER observations (PNST)
Le Contel O., Roux A., Perraut S., Pellat R., Robert P., Chanteur G., Fontaine D., Sauvaud J.-A., Andre M., Balogh A., Cornilleau-Wehrlin N., Fazakerley A., Reme H.
Local as well as global changes of the magnetic field topology in the magnetotail have been observed by the four spacecrafts CLUSTER. The very short timescales and the specific spatial structures of these changes of topology do not correspond to the classical view associated with the formation of a X line by a tearing instability. We suggest a new mechanism based on an instability driven by a parallel current and we test it against CLUSTER observations.