Search Publications
Centrifugal acceleration in the magnetotail lobes
Nilsson, H.; Eriksson, A.; Engwall, E. +2 more
Combined Cluster EFW and EDI measurements have shown that cold ion outflow in the magnetospheric lobes dominates the hydrogen ion outflow from the Earth's atmosphere. The ions have too low kinetic energy to be measurable with particle instruments, at least for the typical spacecraft potential of a sunlit spacecraft in the tenuous lobe plasmas outs…
Cluster-C1 observations on the geometrical structure of linear magnetic holes in the solar wind at 1 AU
Zhang, T. L.; Lucek, E.; Reme, H. +9 more
Interplanetary linear magnetic holes (LMHs) are structures in which the magnetic field magnitude decreases with little change in the field direction. They are a 10-30% subset of all interplanetary magnetic holes (MHs). Using magnetic field and plasma measurements obtained by Cluster-C1, we surveyed the LMHs in the solar wind at 1 AU. In total 567 …
Interplanetary shock transmitted into the Earth's magnetosheath: Cluster and Double Star observations
Rème, H.; Cao, J. B.; Carr, C. M. +4 more
On day 7 May 2005, the plasma instruments on board Double Star TC1 and Cluster SC3 spacecraft register inside the magnetosheath, at 19:15:12 and 19:16:20 UT, respectively, a strong pressure pulse due to the impact of an interplanetary shock wave (IS) on the terrestrial bow shock. The analysis of this event provides clear and quantitative evidences…
Spectral characteristics of protons in the Earth's plasmasheet: statistical results from Cluster CIS and RAPID
Fränz, M.; Dandouras, I.; Daly, P. W. +4 more
We present a study of the spectral characteristics of protons in the Earth's plasma sheet for various geomagnetic disturbance levels. The study is based on about 5400 h of data combined from the Cluster RAPID and CIS instruments obtained during the tail season (July-October). The overall proton spectral shape is generally that of a κ distribution,…
Inertial-range spectrum of whistler turbulence
Narita, Y.; Gary, S. P.
We develop a theoretical model of an inertial-range energy spectrum for homogeneous whistler turbulence. The theory is a generalization of the Iroshnikov-Kraichnan concept of the inertial-range magnetohydrodynamic turbulence. In the model the dispersion relation is used to derive scaling laws for whistler waves at highly oblique propagation with r…
Energetic electrons in the exterior cusp: identifying the source
Chen, J.; Fritz, T. A.; Walsh, B. M. +1 more
A case study is presented to test the role several different sources may play in populating the exterior cusp with energetic (E>40 keV) electrons. The properties of the electrons measured in the exterior cusp are compared with the expected signatures of three sources in order to weigh the role each source may contribute in populating this regio…
Comparison of eight years magnetic field data from Cluster with Tsyganenko models in the inner magnetosphere
Woodfield, E. E.; Dunlop, M. W.; Zhang, Q. -H. +1 more
Eight years of magnetic field data, taken while the four Cluster spacecraft pass through, or adjacent to, the equatorial ring current, have been surveyed to investigate the effects on the Earth's magnetic field of the externally driven current systems connecting the ionosphere, cusp and ring current regions. This study extends previous work to cov…
Global reconnection topology as inferred from plasma observations inside Kelvin-Helmholtz vortices
Dandouras, I.; Lucek, E.; Kistler, L. M. +4 more
During a long lasting period of northward interplanetary magnetic field and high solar wind speed (above 700 km/s), the Cluster spacecraft go across a number of very large rolled-up Kelvin-Helmholtz (KH) vortices at the dusk magnetopause, close to the terminator. The peculiarity of the present event is a particular sequence of ions and electrons d…
Large-scale fluctuations of PSBL magnetic flux tubes induced by the field-aligned motion of highly accelerated ions
Zelenyi, L. M.; Sauvaud, J. -A.; Grigorenko, E. E. +2 more
We present a comprehensive analysis of magnetic field and plasma data measured in the course of 170 crossings of the lobeward edge of Plasma Sheet Boundary Layer (PSBL) in the Earth's magnetotail by Cluster spacecraft. We found that large-scale fluctuations of the magnetic flux tubes have been registered during intervals of propagation of high vel…
On arc-polarized structures in the solar wind
Haaland, S. E.; Paschmann, G.; Sonnerup, B. U. Ö.
A theoretical model is proposed to account for some of the behavior of arc-polarized magnetic structures seen in the solar wind. To this end, an exact analytical solution is developed that describes infinite plane wave trains of arbitrary amplitude in a plasma governed by ideal Hall MHD. The main focus is on intermediate-mode wave trains, which di…