Variations in polar rain flux according to IMF geometries observed by STSAT-1

2012 ◽  
Vol 50 (2) ◽  
pp. 221-227 ◽  
Author(s):  
Jinhy Hong ◽  
J.J. Lee ◽  
K.W. Min ◽  
V.P. Kim ◽  
V.V. Hegai
Keyword(s):  
1997 ◽  
Vol 102 (A2) ◽  
pp. 2271-2278 ◽  
Author(s):  
H. Shirai ◽  
K. Maezawa ◽  
M. Fujimoto ◽  
T. Mukai ◽  
T. Yamamoto ◽  
...  
Keyword(s):  

1984 ◽  
Vol 89 (A11) ◽  
pp. 9785 ◽  
Author(s):  
M. S. Gussenhoven ◽  
D. A. Hardy ◽  
N. Heinemann ◽  
R. K. Burkhardt
Keyword(s):  

1986 ◽  
Vol 91 (A10) ◽  
pp. 11123 ◽  
Author(s):  
M. E. Greenspan ◽  
C.-I. Meng ◽  
D. H. Fairfield
Keyword(s):  

2010 ◽  
Vol 28 (4) ◽  
pp. 1023-1042 ◽  
Author(s):  
P. E. Sandholt ◽  
Y. Andalsvik ◽  
C. J. Farrugia

Abstract. 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 2007 and 17 December 2008 during solar minimum. Focus is placed on two intervals of southward magnetic cloud field with large negative By components (Bx=−5 versus 0 nT) and with high and low plasma densities, respectively, as detected by spacecraft Wind. The convection/precipitation states are documented by DMSP spacecraft (Southern Hemisphere) and SuperDARN radars (Northern Hemisphere). The (negative) By component of the cloud field is accompanied by a newly-discovered flow channel (called here FC 2) threaded by old open field lines (in polar rain precipitation) at the dusk and dawn sides of the polar cap in the Northern and Southern Hemispheres, respectively, and a corresponding Svalgaard-Mansurov (S-M) effect in ground magnetic deflections. On 20 November 2007 the latter S-M effect in the Northern winter Hemisphere appears in the form of a sequence of six 5–10 min long magnetic deflection events in the 71–74° MLAT/14:30–16:00 MLT sector. The X-deflections are consistent with the flow direction in FC 2 (i.e. caused by Hall currents) in both IP cloud cases. The presence of a lobe cell and associated polar arcs in the Southern (summer) Hemisphere in the low density (1–2 cm−3) and Bx=0 ICME case is accompanied by the dropout of polar rain precipitation in the dusk-side regime of sunward polar cap convection and inward-directed Birkeland current. The low-altitude observations are discussed in terms of momentum transfer via dynamo processes in the high- and low-latitude boundary layers and Birkeland currents located poleward of the traditional R1-R2 system.


2007 ◽  
Vol 34 (20) ◽  
Author(s):  
Yongliang Zhang ◽  
Larry J. Paxton ◽  
Anthony T. Y. Lui
Keyword(s):  

2006 ◽  
Vol 33 (19) ◽  
Author(s):  
I. V. Alexeev ◽  
V. Sergeev ◽  
C. J. Owen ◽  
A. Fazakerley ◽  
E. Lucek ◽  
...  

2020 ◽  
Author(s):  
Victor Sergeev ◽  
Sergey Apatenkov ◽  
Rumi Nakamura ◽  
Simon Wellenzohn ◽  
Ferdinand Plaschke ◽  
...  

<p>The region surrounding the reconnection separatrix consists of the multitude of particle and wave transient features (electron, cold and hot ion beams, Hall E&B fields, kinetic Alfven and LH waves, e-holes etc) whose pattern and intensities may vary depending on the stage of reconnection process as well as on the distance from the active neutral line (XNL), whose characterization from observations is not a trivial task. We explore quick MMS entries into the plasma sheet boundary layer from the lobe in 2017 and 2018 tail seasons which potentially could be the crossings of the active separatrix as suggested by energy dispersed beams and polar rain gap features. By combining  the observations of beam dispersion with the measured plasma convection and PSBL motion (obtained using the timing method) we attempt to separate  temporal and spatial (velocity filter) contributions  to the observed beam energy dispersion and evaluate the MMS distance from the XNL. In this report we discuss similarities and differences of separatrix manifestations  observed far from the XNL (at distances exceeding several tens Re) and those found close to it (where the outermost electron beam directed toward the XNL is seen).  One of surprizes was that we were often able to identify the intense Hall-like E&B field structures at very large distances from the XNL.  </p>


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