TY - JOUR

T1 - Extreme Field-Aligned Currents during Magnetic Storms of the 24th Solar Cycle

T2 - March 2015 and September 2017

AU - Lukianova, R. Yu

N1 - Publisher Copyright: © 2020, Pleiades Publishing, Ltd. Copyright: Copyright 2020 Elsevier B.V., All rights reserved.

PY - 2020/3/1

Y1 - 2020/3/1

N2 - Abstract: Characteristics of field-aligned currents (FACs) obtained from the observations of SWARM satellites during two strong magnetic storms in March 16–19, 2015 and September 6–9, 2017 are presented. The storms were accompanied by high-intensity substorms. Satellites crossed the dusk, noon, pre- and after midnight MLT sectors. It was shown that variations in FAC density and the latitudinal position of the equatorial FAC boundaries are controlled by both the development of the storm and, to a considerable degree, substorm activity. The average densities of downward and upward FACs reach 3–4 μA/m2 at a substorm’s peak, while the undisturbed level is about 0.2 μA/m2. The minimum latitude of equatorial FAC boundaries is limited to 50° MLat. Large-scale FACs consist of small-scale filamentary structures with high current density, which are always present in SWARM observations. Small-scale peak currents with a density of 50–100 µA/m2 appear during periods of a general increase in density during activation of substorms. Local increases in concentration and temperature of electrons show that the current structure can be associated with a mesoscale discrete auroral arc.

AB - Abstract: Characteristics of field-aligned currents (FACs) obtained from the observations of SWARM satellites during two strong magnetic storms in March 16–19, 2015 and September 6–9, 2017 are presented. The storms were accompanied by high-intensity substorms. Satellites crossed the dusk, noon, pre- and after midnight MLT sectors. It was shown that variations in FAC density and the latitudinal position of the equatorial FAC boundaries are controlled by both the development of the storm and, to a considerable degree, substorm activity. The average densities of downward and upward FACs reach 3–4 μA/m2 at a substorm’s peak, while the undisturbed level is about 0.2 μA/m2. The minimum latitude of equatorial FAC boundaries is limited to 50° MLat. Large-scale FACs consist of small-scale filamentary structures with high current density, which are always present in SWARM observations. Small-scale peak currents with a density of 50–100 µA/m2 appear during periods of a general increase in density during activation of substorms. Local increases in concentration and temperature of electrons show that the current structure can be associated with a mesoscale discrete auroral arc.

UR - http://www.scopus.com/inward/record.url?scp=85083092695&partnerID=8YFLogxK

U2 - 10.1134/S0010952520020069

DO - 10.1134/S0010952520020069

M3 - Article

AN - SCOPUS:85083092695

VL - 58

SP - 65

EP - 78

JO - Cosmic Research

JF - Cosmic Research

SN - 0010-9525

IS - 2

ER -