Search Publications
Relationship between solar wind low-energy energetic ion enhancements and large geomagnetic storms
Smith, Z.; Murtagh, W.; Smithtro, C.
It is well established that energetic ion enhancements (an energetic ion enhancement will hereafter be referred to as an EIE) are partly due to acceleration by interplanetary shocks as the shocks propagate towards Earth and that arrivals of these shocks at Earth are well associated with geomagnetic storms. The observation of EIEs at satellites loc…
Flow shear near the boundary of the plasma sheet observed by Cluster and Geotail
Balogh, A.; RèMe, H.; Fazakerley, A. N. +13 more
We report on the transient strong flow shear (large northward/southward electric field) events accompanied by energetic ion beams and localized field-aligned currents observed at the boundary of the premidnight plasma sheet by Cluster in the Northern Hemisphere and Geotail in the Southern Hemisphere. The events took place associated with plasma sh…
Cluster measurements of rapidly moving sources of ELF/VLF chorus
Gurnett, D. A.; Pickett, J. S.; Inan, U. S. +2 more
The first simultaneous measurements of discrete chorus emissions on multiple spacecraft, realized in the context of the Cluster mission, revealed a rather unexpected frequency difference of around 1 kHz between nearly identical discrete elements observed on different spacecraft [, 2001]. This frequency difference is interpreted herein as a natural…
Potential barrier in the electrostatic sheath around a magnetospheric spacecraft
Laakso, H.; Escoubet, P.; Hilgers, A. +4 more
Plasma and field measurements on board magnetospheric spacecraft can be influenced by the spacecraft potential and emitted particles such as photoelectrons and secondary electrons. There exist contradictory requirements for, on one hand, minimizing the spacecraft potential and, on the other hand, minimizing perturbations in the sheath and contamin…
New properties of energy-dispersed ions in the plasma sheet boundary layer observed by Cluster
Lundin, R.; Sauvaud, J. -A.; Escoubet, C. P. +18 more
Using multipoint measurements from the Cluster ion spectrometry instruments and the research with adaptive particle imaging detectors, we identified new properties of multiple energy-dispersed ion structures in the plasma sheet boundary layer (PSBL). On 14 February 2001 at about 4.5 RE midnight local time, the PSBL was highly structured…
Energetic magnetospheric oxygen in the magnetosheath and its response to IMF orientation: Cluster observations
Lundin, R.; Sauvaud, J. -A.; Balogh, A. +17 more
We present Cluster observations made during an outbound orbit on 10 December 2000. After exiting the magnetosphere at midlatitude, Cluster spent a long time skimming the magnetopause moving to lower latitude along an orbit approximately in the ZYGSM plane on the dusk flank of the magnetopause. During this time, magnetospheric oxygen wit…
Orientation and motion of a discontinuity from single-spacecraft measurements of plasma velocity and density: Minimum mass flux residue
Balogh, A.; Lavraud, B.; Dunlop, M. W. +4 more
A simple analytical solution is presented to the problem of determining the orientation and motion of a one-dimensional discontinuity in plasma velocity and density, measured by a single spacecraft as the discontinuity moves past it. The method developed is called Minimum Massflux Residue (MMR). Illustrations of the method, based on Cluster measur…
Energetic neutral atoms from Jupiter measured with the Cassini magnetospheric imaging instrument: Time dependence and composition
Krimigis, S. M.; Mitchell, D. G.; Roelof, E. C. +2 more
During the Cassini spacecraft flyby of Jupiter in late 2000/early 2001, the Ion and Neutral Camera (INCA, one of three sensors that make up the Cassini Magnetospheric Imaging Instrument (MIMI)) obtained the first ever images of Jupiter's magnetosphere in energetic neutral atom (ENA) flux. These emissions are dominated by hydrogen atoms in the ener…
On the evolution of the solar wind between 1 and 5 AU at the time of the Cassini Jupiter flyby: Multispacecraft observations of interplanetary coronal mass ejections including the formation of a merged interaction region
Dougherty, M. K.; Young, D. T.; Owens, M. J. +5 more
The Cassini flyby of Jupiter occurred at a time near solar maximum. Consequently, the pre-Jupiter data set reveals clear and numerous transient perturbations to the Parker Spiral solar wind structure. Limited plasma data are available at Cassini for this period due to pointing restrictions imposed on the instrument. This renders the identification…
Derivation of electric potential patterns in the inner magnetosphere from Cluster EDI data: Initial results
Torbert, R. B.; Matsui, H.; Quinn, J. M. +2 more
Electric potential patterns are derived in the inner magnetosphere at 4 < L < 10 using 2 years of data from the Electron Drift Instrument (EDI) on Cluster. First, we examine the relations between the electric field and the following three parameters to understand how the potential patterns are organized: BZ component of the interp…