Search Publications
Spatial and temporal characteristics of poloidal waves in the terrestrial plasmasphere: a CLUSTER case study
Pierrard, V.; Glassmeier, K. H.; Blomberg, L. G. +3 more
Oscillating magnetic field lines are frequently observed by spacecraft in the terrestrial and other planetary magnetospheres. The CLUSTER mission is a very suitable tool to further study these Alfvén waves as the four CLUSTER spacecraft provide for an opportunity to separate spatial and temporal structures in the terrestrial magnetosphere. Using a…
Least-squares gradient calculation from multi-point observations of scalar and vector fields: methodology and applications with Cluster in the plasmasphere
Dunlop, M. W.; de Keyser, J.; Décréau, P. M. E. +1 more
This paper describes a general-purpose algorithm for computing the gradients in space and time of a scalar field, a vector field, or a divergence-free vector field, from in situ measurements by one or more spacecraft. The algorithm provides total error estimates on the computed gradient, including the effects of measurement errors, the errors due …
Comparison of plasma data from ASPERA-3/Mars-Express with a 3-D hybrid simulation
Barabash, S.; Lundin, R.; Krupp, N. +8 more
The ELS and IMA sensors of the ASPERA-3 experiment onboard of Mars-Express (MEX) can measure electron as well as ion moments. We compare these measurements for a specific orbit with the simulation results from a 3-D hybrid model. In the hybrid approximation the electrons are modeled as a massless charge-neutralizing fluid, whereas the ions are tre…
Scattering of field-aligned beam ions upstream of Earth's bow shock
Klecker, B.; Lucek, E. A.; Rème, H. +3 more
Field-aligned beams are known to originate from the quasi-perpendicular side of the Earth's bow shock, while the diffuse ion population consists of accelerated ions at the quasi-parallel side of the bow shock. The two distinct ion populations show typical characteristics in their velocity space distributions. By using particle and magnetic field m…
Proton temperature anisotropy in the magnetosheath: comparison of 3-D MHD modelling with Cluster data
Maksimovic, M.; Alexandrova, O.; Lacombe, C. +2 more
We study four intervals of Cluster data, lasting from five to eight hours, in the flanks of the magnetosheath. In a first part, we make numerical simulations of these magnetosheath crossings, using a three-dimensional double-adiabatic MHD model of the magnetosheath and assuming that the proton temperature anisotropy is bounded by the kinetic thres…
Coherent whistler emissions in the magnetosphere - Cluster observations
Balogh, A.; Dandouras, I.; Lucek, E. +11 more
The STAFF-SC observations complemented by the data from other instruments on Cluster spacecraft were used to study the main properties of magnetospheric lion roars: sporadic bursts of whistler emissions at f~0.1-0.2fe where fe is the electron gyrofrequency. Magnetospheric lion roars are shown to be similar to the emissions in…
Global and local disturbances in the magnetotail during reconnection
Nakamura, R.; Lucek, E. A.; Rème, H. +2 more
We examine Cluster observations of a reconnection event at xGSM=-15.7 RE in the magnetotail on 11 October 2001, when Cluster recorded the current sheet for an extended period including the entire duration of the reconnection event. The onset of reconnection is associated with a sudden orientation change of the ambient magneti…
On the location of dayside magnetic reconnection during an interval of duskward oriented IMF
Balogh, A.; Davies, J. A.; Wild, J. A. +7 more
We present space- and ground-based observations of the signatures of magnetic reconnection during an interval of duskward-oriented interplanetary magnetic field on 25 March 2004. In situ field and plasma measurements are drawn from the Double Star and Cluster satellites during traversals of the pre-noon sector dayside magnetopause at low and high …
CLUSTER observations of electron outflowing beams carrying downward currents above the polar cap by northward IMF
Sauvaud, J. -A.; Maggiolo, R.; Fazakerley, A. +3 more
Above the polar cap, at about 5-9 Earth radii (RE) altitude, the PEACE experiment onboard CLUSTER detected, for the first time, electron beams outflowing from the ionosphere with large and variable energy fluxes, well collimated along the magnetic field lines. All these events occurred during periods of northward or weak interplanetary …
Near-simultaneous magnetotail flux rope observations with Cluster and Double Star
Wilson, R. J.; Dandouras, I.; Lucek, E. +6 more
We present observations of three magnetic flux ropes in the tail of the Earth's magnetosphere on 7 August 2004 by the Cluster and Double Star TC-1 spacecraft. The first two flux rope signatures were observed, near-simultaneously, by Cluster and TC-1, which were located at (-16.3, -8.7, 0.10) RE GSM and (-10.3, -7.11, 0.81) RE…