A flux transfer event observed at the magnetopause by the Equator-S spacecraft and in the ionosphere by the CUTLASS HF radar

D. A. Neudegg (1) , T. K. Yeoman (1) , S. W. H. Cowley (1) , G. Provan (1) , G. Haerendel (2) , W. Baumjohann (2) , U. Auster (3) , K.-H. Fornacon (3) , E. Georgescu (4) , C. J. Owen (5)

1 Department of Physics and Astronomy [Leicester]
2 MPE - Max-Planck-Institut für Extraterrestrische Physik
3 Technische Universität Braunschweig = Technical University of Braunschweig [Braunschweig]
4 ISS
5 Queen Mary and Westfield College

Observations of a flux transfer event (FTE) have been made simultaneously by the Equator-S spacecraft near the dayside magnetopause whilst corresponding transient plasma flows were seen in the near-conjugate polar ionosphere by the CUTLASS Finland HF radar. Prior to the occurrence of the FTE, the magnetometer on the WIND spacecraft ~226 R_E upstream of the Earth in the solar wind detected a southward turning of the interplanetary magnetic field (IMF) which is estimated to have reached the subsolar magnetopause ~77 min later. Shortly afterwards the Equator-S magnetometer observed a typical bipolar FTE signature in the magnetic field component normal to the magnetopause, just inside the magnetosphere. Almost simultaneously the CUTLASS Finland radar observed a strong transient flow in the F region plasma between 78° and 83° magnetic latitude, near the ionospheric region predicted to map along geomagnetic field lines to the spacecraft. The flow signature (and the data set as a whole) is found to be fully consistent with the view that the FTE was formed by a burst of magnetopause reconnection.

Domaines: Océan, Atmosphère; Sciences de la Terre

D. A. Neudegg, T. K. Yeoman, S. W. H. Cowley, G. Provan, G. Haerendel, et al.. A flux transfer event observed at the magnetopause by the Equator-S spacecraft and in the ionosphere by the CUTLASS HF radar. Annales Geophysicae, 1999, 17 (6), pp.707-711. ⟨hal-00316604⟩