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AbstractAbstract
[en] Complex experiment covering satellite radioscopy and vertical probing of ionosphere is carried out to obtain a comprehensive range of parameters characterizing average-scale moving ionosphere disturbances
Original Title
Variatsii parametrov volnovykh struktur v ionosfere po dannym kompleksnogo ehksperimenta za period SUNDIAL sentyabr' -oktyabr' 1989 g
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[en] A three-dimensional ray-tracing analysis is employed to calculate ray paths through a model ionosphere which itself is perturbed by the passage of horizontally moving wavelike disturbance. A knowledge of various parameters (e.g. phase and group paths, angle of arrival, Doppler frequency shift) for ray paths connecting a central transmitter with spaced receivers permits an evaluation of several spaced-station techniques for measuring horizontal phase velocities of travelling ionospheric disturbances (TIDs). It is shown that in experiments with transmitter-receiver spacings of less than 150 km, reliable velocity estimates may be expected, even though the assumption of a horizontally stratified ionosphere which is common to all methods is strictly invalid. (author)
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Australian Inst. of Physics, Parkville; p. 10; Apr 1974; Australian Institute of Physics national congress; Adelaide, Australia; 21 May 1974; Paper UM6, abstract only.
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Chi, P.J.; Spasojevic, M.
International Association of Geomagnetism and Aeronomy IAGA 11. Scientific Assembly2009
International Association of Geomagnetism and Aeronomy IAGA 11. Scientific Assembly2009
AbstractAbstract
[en] Complete text of publication follows. First discovered by Chung Park in 1973, the plasmasphere within the new plasmaspheric boundary layer during magnetic storms could undergo a noticeable decrease in density, and this depletion could represent a significant fraction of the overall losses from the plasmasphere. Several processes, such as plasma dumping to the ionosphere, have been proposed as the cause of internal plasmaspheric depletion during storm times, but finding the responsible physical mechanism remains an outstanding problem. As an effort to identify the important causes to this complicated phenomenon, this study examines a collection of critical ground and satellite observations, including the mass density inferred from field line resonance sounding, the charge density deduced from whistler traces, ionosonde data, and the RPI observations from the IMAGE satellite. We find that the plasmasphere within the new plasmaspheric boundary layer does not necessarily decrease in all magnetic storms. An enhancement in plasmaspheric density can sometimes be found. The increase or decrease in plasmaspheric density echoes the change in ionospheric content during the storm event. Our results suggest that, during magnetic storms, the related ionospheric storms may play a major role controlling the internal plasmaspheric content.
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Geodetic and Geophysical Research Institute of the Hungarian Academy of Sciences (ed.); [1212 p.]; 2009; [1 p.]; International Association of Geomagnetism and Aeronomy IAGA 11. Scientific Assembly; Sopron (Hungary); 23-30 Aug 2009; Available from http://www.iaga2009sopron.hu
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AbstractAbstract
[en] Analysis of the experimental data on the ionosphere probing using various methods in different regions proves the hypothesis about the occurrence of the isolated large-scale moving disturbances of the electron density with 500-3000 km dimensions within 200-2000 km high-altitude range. Disturbances are of nonlinear nature and affect essentially various range radio-signals
Original Title
Krupnomasshtabnye izolirovannye vozmushcheniya ehlektronnoj kontsentratsii ionosfery v okrestnostyakh glavnogo maksimuma
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10 refs.
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AbstractAbstract
No abstract available
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Journal of Geophysical Research; v. 79(25); p. 3827-3833
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[en] The statistical features of field-aligned currents include the following: (1) The large-scale regions of field-aligned currents determined previously persist during all phases of substorm activity. Namely, region 1 located near the poleward boundary of the field-aligned current region and region 2 located near the equatorward boundary. Field-aligned currents flow into region 1 on the morning side and away from region 1 on the evening side. The current flow in region 2 is reversed to region 1 at any given local time except in the Harang discontinuity region (-- 2000 - 2400 MLT) where the flow patterns are more complicated. (2) During active periods, the average latitude width of regions 1 and 2 increases by 20% to 30% and the centers of these regions shift equatorward by 20 to 30 with respect to the quiet time values. (3) The current density is statistically larger in region 1 than in region 2 at all local times except during active periods and in the midnight to morning local time sector. (4) During relatively quiet conditions, the largest field-aligned current densities occur in two areas of region 1 near noon (near -- 1030 MLT and -- 1300 MLT) with an average value of -- 1.6 μamp/m2. During active periods, the regions of peak current density shift toward the nightside (the region near 1030 MLT shifts to --0730 MLT, and the region near 1300 MLT shifts to -- 1430 MLT) and the average current density increases to -- 2.2 μamp/m2. (5) The average total amount of field-aligned current flowing into the ionosphere always equals the current flow away from the ionosphere during a wide range of quiet and disturbed conditions. (6) A three-region pattern of field-aligned current flow persists in the Harang discontinuity region (-- 2000 - 2400 MLT) during undisturbed and disturbed periods when the westward auroral electrojet does not intrude into this sector. (J.P.N.)
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Tokyo Univ. (Japan). Inst. of Space and Aeronautical Science; p. 145-180; 1977; p. 145-180; Tokyo Univ. Inst. of Space and Aeronautical Science; Tokyo, Japan; IMS symposium; Tokyo, Japan; 14 - 16 Jul 1977
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Bonelli, E.; Medeiros, R.T. de; Nelson, O.R.; Borba, G.L.
Proceedings of the 1. Brazilian Symposium on Space Plasma-Abstracts1987
Proceedings of the 1. Brazilian Symposium on Space Plasma-Abstracts1987
AbstractAbstract
[en] Published in summary form only
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Instituto de Pesquisas Espaciais, Sao Jose dos Campos (Brazil); 152 p; 1987; p. 89; 1. Brazilian Symposium on Space Plasma; Sao Jose dos Campos, SP (Brazil); 8-11 Sep 1987
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AbstractAbstract
[en] The ionospheric disturbances around Japan associated with the severe magnetic storm on July 14-16, 1982 were investigated using ionospheric total electron content (Nsub(t)) data obtained by the ETS-II beacon experiment and F-region data obtained by the soundings at the latitude chain of the ionospheric stations situated nearly along 135 0E. The most remarkable storm effects were the negative disturbances, which are common at mid-latitudes in summer. The negative disturbances comprise decreases in Nsub(t) and peak electron density (Nsub(m)) and a marked increase in slab thickness. In addition, the following interesting events were observed during this storm: (1) sharp decreases in Nsub(t) and Nsub(m) occurred almost simultaneously in the regions from mid-latitudes to the equatorial latitude within a few hours after the storm sudden commencement (SSC), (2) some positive disturbances in the F-region appeared during the last phase of the storm, which were prominent at mid-latitudes during the night and at low-latitudes in the afternoon, and (3) a medium-scale traveling ionospheric distubance (TID) with a nearly north to south direction of propagation was observed as wavelike fluctuations of Nsub(t). (author)
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AbstractAbstract
No abstract available
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Letter to the editor.
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Nature (London); v. 250(5463); p. 205-206
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No abstract available
Original Title
O svyazi magnitosfernykh i ionosfernykh vozmushchenij vo vremya geomagnitnoj buri
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AN SSSR, Moscow. Inst. Zemnogo Magnetizma, Ionosfery i Rasprostraneniya Radiovoln; p. 89; 1979; p. 89; Symposium CAPG on solar-terrestrial physics; Ashkhabad, USSR; 22 - 28 Oct 1979; Short note.
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