Search Publications
Cluster observations of the high-latitude magnetopause and cusp: initial results from the CIS ion instruments
Lundin, R.; Sauvaud, J. -A.; Escoubet, C. P. +22 more
Launched on an elliptical high inclination orbit (apogee: 19.6 RE) since January 2001 the Cluster satellites have been conducting the first detailed three-dimensional studies of the high-latitude dayside magnetosphere, including the exterior cusp, neighbouring boundary layers and magnetopause regions. Cluster satellites carry the CIS ion spectrome…
Multi-spacecraft observations of broadband waves near the lower hybrid frequency at the Earthward edge of the magnetopause
Balogh, A.; Wahlund, J. -E.; Lucek, E. +18 more
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. …
Polarisation and propagation of lion roars in the dusk side magnetosheath
Balogh, A.; Dandouras, I.; Maksimovic, M. +8 more
We present observations of lion roars obtained in the magnetosheath by the Spectrum Analyser (SA) of the Spatio-Temporal Analysis of Field Fluctuations (STAFF) experiment aboard Cluster. STAFF-SA calculates, in near real time, the complete auto- and cross-spectral matrix derived from three magnetic and two electric components of the electromagneti…
Coordinated Cluster and ground-based instrument observations of transient changes in the magnetopause boundary layer during an interval of predominantly northward IMF: relation to reconnection pulses and FTE signatures
Pitout, F.; Balogh, A.; Wild, J. A. +35 more
We study a series of transient entries into the low-latitude boundary layer (LLBL) of all four Cluster spacecraft during an outbound pass through the mid-afternoon magnetopause ( [ XGSM, YGSM, ZGSM ] <approx> [ 2, 7, 9 ] RE). The events take place during an interval of northward IMF, as seen in the data from the ACE satellite and lagged by a…
Identification of natural plasma emissions observed close to the plasmapause by the Cluster-Whisper relaxation sounder
Fergeau, P.; Décréau, P. M. E.; Canu, P. +9 more
We use the data collected by the Whisper instrument onboard the Cluster spacecraft for a first test of its capabilities in the identification of the natural plasma waves observed in the Earth's magnetosphere. The main signatures observed at the plasma frequency, upper hybrid frequency, and electron Bernstein modes were often difficult to be reliab…
Cluster observes the Earth's magnetopause: coordinated four-point magnetic field measurements
Balogh, A.; Dunlop, M. W.; Cargill, P. +5 more
The four-spacecraft Cluster mission has provided high-time resolution measurements of the magnetic field from closely maintained separation distances (200-600 km). Four-point coverage of the Earth's magnetopause began on the 9 and 10 November 2000 when all spacecraft first exited the dusk-side magnetosphere at about 19:00 LT, providing extensive c…
Coordinated Cluster, ground-based instrumentation and low-altitude satellite observations of transient poleward-moving events in the ionosphere and in the tail lobe
Pitout, F.; Balogh, A.; Wild, J. A. +35 more
During the interval between 8:00-9:30 on 14 January 2001, the four Cluster spacecraft were moving from the central magnetospheric lobe, through the dusk sector mantle, on their way towards intersecting the magnetopause near 15:00 MLT and 15:00 UT. Throughout this interval, the EISCAT Svalbard Radar (ESR) at Longyearbyen observed a series of polewa…
Cluster EDI convection measurements across the high-latitude plasma sheet boundary at midnight
Baumjohann, W.; Torbert, R. B.; Matsui, H. +15 more
We examine two crossings of three Cluster satellites from the polar cap into the high-latitude plasma sheet at midnight local time, using data from the Electron Drift Instrument (EDI). EDI measures the full electron drift velocity in the plane perpendicular to the magnetic field for any field and drift directions. The context of the measured conve…
Cluster boundary layer measurements and optical observations at magnetically conjugate sites
Lucek, E.; André, M.; Lybekk, B. +7 more
The Cluster spacecraft experienced several boundary layer encounters when flying outbound from the magnetosphere to the magnetosheath in the dusk sector on 14 January 2001. The dayside boundary layer was populated by magnetosheath electrons, but not with quite as high densities as in the magnetosheath itself. The Cluster ground track was calculate…
Observations of the cusp region under northward IMF
Pitout, F.; Rème, H.; Alcaydé, D. +2 more
We present a comparative study of the cusp region using the EISCAT Svalbard Radars (ESR) and the Cluster spacecraft. We focus in this paper on 2 February 2001, over the time period from 07:30 UT to 12:00 UT when the oblique ESR antenna pointing northward at a low elevation recorded latitudinal motions of the cusp region in response to the IMF. Mea…