Results 1 to 10 of about 203,115 (295)
HF radar polar patch formation revisited: summer and winter variations in dayside plasma structuring [PDF]
Annales Geophysicae, 2002 Three intervals of polar patch formation, as observed by the CUTLASS Finland HF coherent radar, are presented. Simultaneous observations from a vertical ionosonde located at Longyearbyen on Svalbard, situated in the dayside convection throat region,
S. E. Milan +3 more
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Polar cap arcs from the magnetosphere to the ionosphere: kinetic modelling and observations by Cluster and TIMED [PDF]
Annales Geophysicae, 2012 On 1 April 2004 the GUVI imager onboard the TIMED spacecraft spots an isolated and elongated polar cap arc. About 20 min later, the Cluster satellites detect an isolated upflowing ion beam above the polar cap.
R. Maggiolo +7 more
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Combined ESR and EISCAT observations of the dayside polar cap and auroral oval during the May 15, 1997 storm [PDF]
Annales Geophysicae, 2000 The high-latitude ionospheric response to a major magnetic storm on May 15, 1997 is studied and different responses in the polar cap and the auroral oval are highlighted.
H. Liu +6 more
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What if pulsars are born as strange stars? [PDF]
, 2000 The possibility and the implications of the idea, that pulsars are born as strange stars, are explored. Strange stars are very likely to have atmospheres with typical mass of $\sim 5\times 10^{-15}M_\odot$ but bare polar caps almost throughout their ...
Qiao, G. J., Xu, R. X., Zhang, Bing
core +3 more sources
Aurora and open magnetic flux during isolated substorms, sawteeth, and SMC events [PDF]
Annales Geophysicae, 2007 Using Polar UVI LBHl and IMAGE FUV WIC data, we have compared the auroral signatures and polar cap open flux for isolated substorms, sawteeth oscillations, and steady magnetospheric convection (SMC) events.
A. D. DeJong +3 more
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On a new process for cusp irregularity production [PDF]
Annales Geophysicae, 2008 Two plasma instability mechanisms were thought until 2007 to dominate the formation of plasma irregularities in the F region high latitude and polar ionosphere; the gradient-drift driven instability, and the velocity-shear driven instability.
H. C. Carlson +3 more
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The location of the open-closed magnetic field line boundary in the dawn sector auroral ionosphere [PDF]
Annales Geophysicae, 2004 As a measure of the degree of coupling between the solar wind-magnetosphere-ionosphere systems, the rate at which the size of the polar cap (the region corresponding to ionospheric termini of open magnetic flux tubes) varies is of prime importance ...
J. A. Wild +9 more
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Frontiers in Astronomy and Space Sciences, 2023 Dynamic mesoscale flow structures move across the open field line regions of the polar caps and then enter the nightside plasma sheet where they can cause important space weather disturbances, such as streamers, substorms, and omega bands.
Larry R. Lyons +10 more
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Journal of Space Weather and Space Climate, 2014 We directly compare the relative GPS scintillation levels associated with regions of enhanced plasma irregularities called auroral arcs, polar cap patches, and auroral blobs that frequently occur in the polar ionosphere.
Jin Yaqi +2 more
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IMF effect on sporadic-E layers at two northern polar cap sites: Part I – Statistical study [PDF]
Annales Geophysicae, 2006 In this paper we investigate the relationship between polar cap sporadic-E layers and the direction of the interplanetary magnetic field (IMF) using a 2-year database from Longyearbyen (75.2 CGM Lat, Svalbard) and Thule (85.4 CGM Lat, Greenland). It is
M. Voiculescu +4 more
doaj +1 more source