scholarly journals Rethinking the polar cap: Eccentric dipole structuring of ULF power at the highest corrected geomagnetic latitudes

2016 ◽  
Vol 121 (9) ◽  
pp. 8475-8507 ◽  
Author(s):  
Kevin D. Urban ◽  
Andrew J. Gerrard ◽  
Louis J. Lanzerotti ◽  
Allan T. Weatherwax
Keyword(s):  
Polar Cap ◽  
Eccentric Dipole

A large rotating structure around AB Doradus A at VLBI scale

2019 ◽  
Vol 15 (S354) ◽  
pp. 189-194
Author(s):  
J. B. Climent ◽  
J. C. Guirado ◽  
R. Azulay ◽  
J. M. Marcaide
Keyword(s):  
Magnetic Reconnection ◽  
Main Sequence ◽  
Complex Structure ◽  
Main Sequence Star ◽  
Polar Cap ◽  
Vlbi Observations ◽  
Rotating Structure ◽  
Source Structure ◽  
Expected Position

AbstractWe report the results of three VLBI observations of the pre-main-sequence star AB Doradus A at 8.4 GHz. With almost three years between consecutive observations, we found a complex structure at the expected position of this star for all epochs. Maps at epochs 2007 and 2010 show a double core-halo morphology while the 2013 map reveals three emission peaks with separations between 5 and 18 stellar radii. Furthermore, all maps show a clear variation of the source structure within the observing time. We consider a number of hypothesis in order to explain such observations, mainly: magnetic reconnection in loops on the polar cap, a more general loop scenario and a close companion to AB Dor A.

Ionospheric Conductivity Dependence of the Cross-Polar Cap Potential Difference and Global Joule Heating Rate

1988 ◽  
Author(s):  
B.-H. Ahn ◽  
Y. Kamide ◽  
S.-I. Akasofu ◽  
H. W. Kroehl ◽  
D. J. Gorney
Keyword(s):  
Heating Rate ◽  
Joule Heating ◽  
Potential Difference ◽  
Polar Cap ◽  
Ionospheric Conductivity ◽  
The Cross ◽  
Cross Polar Cap Potential

scholarly journals Deep Learning Models for Estimation of the SuperDARN Cross Polar Cap Potential

2020 ◽  
Vol 7 (8) ◽  
Author(s):  
Erxiao Liu ◽  
Hongqiao Hu ◽  
Jianjun Liu ◽  
Lei Qiao
Keyword(s):  
Deep Learning ◽  
Learning Models ◽  
Polar Cap ◽  
Cross Polar Cap Potential

scholarly journals Space weather challenges of the polar cap ionosphere

2013 ◽  
Vol 3 ◽  
pp. A02 ◽  
Author(s):  
Jøran Moen ◽  
Kjellmar Oksavik ◽  
Lucilla Alfonsi ◽  
Yvonne Daabakk ◽  
Vineenzo Romano ◽  
...  
Keyword(s):  
Space Weather ◽  
Polar Cap

Accelerated Auroral and Polar-Cap Ions : Outflow at De-1 Altitudes

2013 ◽  
pp. 72-76 ◽  
Author(s):  
A. W. Yau ◽  
E. G. Shelley ◽  
W. K. Peterson
Keyword(s):  
Polar Cap

“Body surface” potentials produced by the eccentric dipole in the heart wall of the nonhomogeneous volume conductor

1963 ◽  
Vol 65 (2) ◽  
pp. 200-207 ◽  
Author(s):  
Robert H. Bayley ◽  
Paul M. Berry
Keyword(s):  
Body Surface ◽  
Volume Conductor ◽  
Surface Potentials ◽  
Heart Wall ◽  
Eccentric Dipole

scholarly journals Kelvin's article on the magnetic centre and Schmidt's one on the optimal eccentric dipole, revisited

2015 ◽  
Vol 347 (2) ◽  
pp. 64-65
Author(s):  
Georges Jobert
Keyword(s):  
Magnetic Centre ◽  
Eccentric Dipole

scholarly journals Observations of AGW/TID propagation across the polar cap: a case study

2011 ◽  
Vol 29 (8) ◽  
pp. 1355-1363 ◽  
Author(s):  
H. T. Cai ◽  
F. Yin ◽  
S. Y. Ma ◽  
I. W. McCrea
Keyword(s):  
Large Scale ◽  
Source Region ◽  
Polar Cap ◽  
Night Time ◽  
F Region ◽  
Atmospheric Disturbances ◽  
Geomagnetic Pole ◽  
Ionization Waves ◽  
North Polar ◽  
Propagation Properties

Abstract. In this paper, we present observational evidence for the trans-polar propagation of large-scale Traveling Ionospheric Disturbances (TIDs) from their nightside source region to the dayside. On 13 February 2001, the 32 m dish of EISCAT Svalbard Radar (ESR) was directing toward the geomagnetic pole at low elevation (30°) during the interval 06:00–12:00 UT (MLT ≈ UT + 3 h), providing an excellent opportunity to monitor the ionosphere F-region over the polar cap. The TIDs were first detected by the ESR over the dayside north polar cap, propagating equatorward, and were subsequently seen by the mainland UHF radar at auroral latitudes around geomagnetic local noon. The propagation properties of the observed ionization waves suggest the presence of a moderately large-scale TIDs, propagating across the northern polar cap from the night-time auroral source during substorm conditions. Our results agree with the theoretical simulations by Balthazor and Moffett (1999) in which poleward-propagating large-scale traveling atmospheric disturbances were found to be self-consistently driven by enhancements in auroral heating.

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