Search Publications
Alfvén Waves and Their Roles in the Dynamics of the Earth's Magnetotail: A Review
Keiling, Andreas
The Earth’s magnetotail is an extremely complex system which—energized by the solar wind—displays many phenomena, and Alfvén waves are essential to its dynamics. While Alfvén waves were first predicted in the early 1940’s and ample observations were later made with rockets and low-altitude satellites, observational evidence of Alfvén waves in diff…
Plasmaspheric Density Structures and Dynamics: Properties Observed by the CLUSTER and IMAGE Missions
de Keyser, Johan; Carpenter, Donald L.; Darrouzet, Fabien +11 more
Plasmaspheric density structures have been studied since the discovery of the plasmasphere in the late 1950s. But the advent of the Cluster and Image missions in 2000 has added substantially to our knowledge of density structures, thanks to the new capabilities of those missions: global imaging with Image and four-point in situ measurements with C…
Recent Progress in Physics-Based Models of the Plasmasphere
André, Nicolas; Jordanova, Vania K.; Lemaire, Joseph F. +5 more
We describe recent progress in physics-based models of the plasmasphere using the fluid and the kinetic approaches. Global modeling of the dynamics and influence of the plasmasphere is presented. Results from global plasmasphere simulations are used to understand and quantify (i) the electric potential pattern and evolution during geomagnetic stor…
Electric Fields and Plasma Processes in the Auroral Downward Current Region, Below, Within, and Above the Acceleration Region
Marklund, G. T.
The downward field-aligned current region plays an active role in magnetosphere-ionosphere coupling processes associated with aurora. A quasi-static electric field structure with a downward parallel electric field forms at altitudes between 800 km and 5000 km, accelerating ionospheric electrons upward, away from the auroral ionosphere. A wealth of…
Augmented Empirical Models of Plasmaspheric Density and Electric Field Using IMAGE and CLUSTER Data
Gallagher, Dennis L.; Tu, Jiannan; Moldwin, Mark B. +4 more
Empirical models for the plasma densities in the inner magnetosphere, including plasmasphere and polar magnetosphere, have been in the past derived from in situ measurements. Such empirical models, however, are still in their initial phase compared to magnetospheric magnetic field models. Recent studies using data from CRRES, Polar, and Image have…
Advances in Plasmaspheric Wave Research with CLUSTER and IMAGE Observations
Carpenter, Donald L.; Darrouzet, Fabien; Grimald, Sandrine +8 more
This paper highlights significant advances in plasmaspheric wave research with Cluster and Image observations. This leap forward was made possible thanks to the new observational capabilities of these space missions. On one hand, the multipoint view of the four Cluster satellites, a unique capability, has enabled the estimation of wave characteris…
Electric Fields and Magnetic Fields in the Plasmasphere: A Perspective From CLUSTER and IMAGE
de Keyser, Johan; Carpenter, Donald L.; Darrouzet, Fabien +7 more
The electric field and magnetic field are basic quantities in the plasmasphere measured since the 1960s. In this review, we first recall conventional wisdom and remaining problems from ground-based whistler measurements. Then we show scientific results from Cluster and Image, which are specifically made possible by newly introduced features on the…
CLUSTER and IMAGE: New Ways to Study the Earth's Plasmasphere
de Keyser, Johan; Carpenter, Donald L.; Darrouzet, Fabien +2 more
Ground-based instruments and a number of space missions have contributed to our knowledge of the plasmasphere since its discovery half a century ago, but it is fair to say that many questions have remained unanswered. Recently, NASA’s Image and ESA’s Cluster probes have introduced new observational concepts, thereby providing a non-local view of t…