Statistical Birkeland current distributions from magnetic field observations by the Iridium constellation [PDF]
Annales Geophysicae, 2008 We present a statistical analysis of Birkeland currents derived from Iridium magnetometer data acquired in the Northern Hemisphere to determine the dependence of large-scale currents on the interplanetary magnetic field (IMF) direction.
B. J. Anderson +4 more
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Comparison of large-scale Birkeland currents determined from Iridium and SuperDARN data [PDF]
Annales Geophysicae, 2006 The Birkeland currents, J||, electrically couple the high latitude ionosphere with the near Earth space environment. Approximating the spatial distribution of the Birkeland currents may be achieved using the divergence of the ionospheric electric ...
D. L. Green +4 more
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Euler potentials for two layers with non-constant current densities in the ambient magnetic field aligned to the layers [PDF]
Annales Geophysicae, 2016 The Euler potentials for two current layers aligned to an ambient homogeneous magnetic field are found. Previous treatment of such a system assumed constant current density in the layers. However, the magnetic field becomes infinite at the edges.
M. Vandas, E. P. Romashets
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Defining and resolving current systems in geospace [PDF]
Annales Geophysicae, 2015 Electric currents flowing through near-Earth space (R ≤ 12 RE) can support a highly distorted magnetic field topology, changing particle drift paths and therefore having a nonlinear feedback on the currents themselves.
N. Y. Ganushkina +19 more
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Polar cap convection/precipitation states during Earth passage of two ICMEs at solar minimum [PDF]
Annales Geophysicae, 2010 We report important new aspects of polar cap convection and precipitation (dawn-dusk and inter-hemisphere asymmetries) associated with the different levels of forcing of the magnetosphere by two interplanetary (IP) magnetic clouds on 20 November ...
P. E. Sandholt +2 more
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The choice of the concept of magnetic field lines or of electric current lines: Alfvén medal lecture [PDF]
Annales Geophysicae, 2011 In 1967, at the Birkeland Symposium in Sandefjord, Norway, Professor Hannes Alfvén stated that the second approach (in solving unsolved problems by the standard MHD theory) to cosmic electrodynamics is to "thaw" the "frozen-in" magnetic field lines ...
S.-I. Akasofu
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Downward ion acceleration at auroral latitudes: cause of parallel electric field [PDF]
Annales Geophysicae, 2002 Observations with the Freja satellite at about 1700 km altitude of downward accelerated ions in the keV and sub-keV energy range are described and analysed.
B. Hultqvist, B. Hultqvist
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Frontiers in Astronomy and Space Sciences, 2023 On the bow shock in front of Earth’s magnetosphere flows a current due to the curl of the interplanetary magnetic field across the shock. The closure of this current remains uncertain; it is unknown whether the bow shock current closes with the Chapman ...
Pauline M. Dredger +2 more
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Observing the Birkeland currents [PDF]
Eos, Transactions American Geophysical Union, 2014 When the supersonic solar wind hits the Earth's magnetic field, a powerful electrical connection occurs with Earth's field, generating millions of amperes of current that drive the dazzling auroras. These so‐called Birkeland currents connect the ionosphere to the magnetosphere and channel solar wind energy to Earth's uppermost atmosphere.
openaire +1 more source
Multi-instrument mapping of the small-scale flow dynamics related to a cusp auroral transient [PDF]
Annales Geophysicae, 2005 In this paper we focus on flux transfer events (FTEs) and poleward moving auroral forms (PMAFs) in the cusp region, combining data from the EISCAT Svalbard radar, SuperDARN HF radars, ground-based optics, and three low-altitude polar-orbiting ...
K. Oksavik +9 more
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