Search Publications
Spatio-temporal structure of storm-time chorus
Gurnett, D. A.; Pickett, J. S.; Parrot, M. +2 more
We discuss chorus emissions measured by the four Cluster spacecraft at close separations during a geomagnetically disturbed period on 18 April 2002. We analyze the lower band of chorus below one half of the electron cyclotron frequency, measured at a radial distance of 4.4 Earth's radii, within a 2000 km long source region located close to the equ…
Analyses on the geometrical structure of magnetic field in the current sheet based on cluster measurements
Balogh, A.; Baker, D. N.; Wang, X. +5 more
The geometrical structure of the magnetic field is a critical character in the magnetospheric dynamics. Using the magnetic field data measured by the Cluster constellation satellites, the geometrical structure including the curvature radius, directions of curvature, and normal of the osculating planes of the magnetic field lines within the current…
ULF wave identification in the magnetosheath: The k-filtering technique applied to Cluster II data
Balogh, A.; Belmont, G.; Sahraoui, F. +8 more
The magnetic fluctuations in the magnetosheath are studied, thanks to Cluster II data. The k-filtering technique is applied to explore ULF magnetic fluctuations using STAFF (Spatio-Temporal Analysis of a Field Fluctuations) data. Based on multipoint measurements, the k-filtering technique allows, for the first time, to estimate the Magnetic Field …
A statistical study of compressional waves in the tail current sheet
Balogh, A.; Zhang, T. L.; Klecker, B. +9 more
A statistical study of the Cluster FGM data is performed on compressional waves for 68 selected 12 min intervals when the spacecraft are in or near the neutral sheet. The data are well distributed in local time between 2100 and 0300 LT. The compressional wave power is strongly dependent on the maximum plasma flow velocity (based on the CIS-CODIF d…
Plasma sheet structure during strongly northward IMF
Petrukovich, A. A.; Balogh, A.; Glassmeier, K. -H. +5 more
On 14 September 2001, under stongly northward IMF conditions Cluster registered several fast magnetic field polarity changes which are usually attributed to thin (near-equatorial) current sheet crossings. However, the IMF was northward for the previous 24 hours, the plasma sheet was expanded vertically, filled with cold, dense plasmas with high lo…
Electric field measurements in the inner magnetosphere by Cluster EDI
Baumjohann, W.; Torbert, R. B.; Matsui, H. +4 more
We report electric field measurements in the inner magnetosphere from the Electron Drift Instrument (EDI) on Cluster at distances of 4 < L < 10. The data used in this study span more than 1 year so that all local times are covered. Both components of the electric field perpendicular to the ambient magnetic field are mapped into the equatoria…
Locations of auroral kilometric radiation bursts inferred from multispacecraft wideband Cluster VLBI observations. 1: Description of technique and initial results
Gurnett, D. A.; Pickett, J. S.; Mutel, R. L. +2 more
The Cluster Wideband Data instrument has been used to determine the locations of auroral kilometric radiation (AKR) using very long baseline interferometry. The technique involves cross-correlating individual AKR bursts from all six Cluster baselines using time and frequency filtered waveforms. The resulting differential delay peaks are used to de…
Cluster observations of the high-altitude cusp for northward interplanetary magnetic field: A case study
Lavraud, B.; Dunlop, M. W.; Bosqued, J. M. +7 more
Since January 2001, the multisatellite and multiinstrument CLUSTER mission gives a unique opportunity to study the structure and dynamics of the high-altitude polar cusp. On 17 March 2001, CLUSTER sampled the northern high-altitude cusp (7-9RE) around noon for more than 1 hour during very quiet interplanetary and magnetospheric conditio…
Tail lobe convection observed by Cluster/EDI
Nakamura, R.; Baumjohann, W.; Noda, H. +7 more
By using drift velocity data measured in the near-Earth tail lobe by the Electron Drift Instrument aboard the Cluster spacecraft, we study the average tail lobe convection of the Earth's magnetosphere. The data confirm the convection pattern toward the neutral sheet in the meridional (XZ) plane. By dividing the data according to the IMF clock angl…
Near-source and remote observations of kilometric continuum radiation from multispacecraft observations
Gurnett, D. A.; Pickett, J. S.; Menietti, J. D. +2 more
Kilometric continuum (KC) radiation was first identified from Geotail plasma wave observations. Past authors have shown that this emission has a frequency range that overlaps that of the auroral kilometric radiation (AKR) but is characterized by a fine structure of narrow-bandwidth, linear features that have nearly constant or drifting frequency. …