Relationship between PC index and magnetospheric field-aligned currents measured by Swarm satellites

О. Troshichev*, D. Sormakov, R. Behlke

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

Abstract The relationship between the magnetospheric field-aligned currents (FAC) monitored by the Swarm satellites and the magnetic activity PC index (which is a proxy of the solar wind energy incoming into the magnetosphere) is examined. It is shown that current intensities measured in the R1 and R2 FAC layers at the poleward and equtorward boundaries of the auroral oval are well correlated, the R2 currents being evidently secondary in relation to R1 currents and correlation in the dawn and dusk oval sectors being better than in the noon and night sectors. There is evident relationship between the PC index and the intensity of field-aligned currents in the R1 dawn and dusk layers: increase of FAC intensity in the course of substorm development is accompanied by increasing the PC index values. Correlation between PC and FAC intensities in the R2 dawn and dusk layers is also observed, but it is much weaker. No correlation is observed between PC and field-aligned currents in the midnight as well as in the noon sectors ahead of the substorm expansion phase. The results are indicative of the R1 field-aligned currents as a driver of the polar cap magnetic activity (PC index) and currents in the R2 layer.
Original languageEnglish
JournalJournal of Atmospheric and Solar-Terrestrial Physics
Volume168
Pages (from-to)37–47
ISSN1364-6826
DOIs
Publication statusPublished - 2018

Keywords

  • Magnetospheric field-aligned currents
  • Auroral oval
  • PC index of magnetic activity
  • Magnetospheric substorms

Cite this

@article{3821d9c2d1ce4746afd16617740943c3,
title = "Relationship between PC index and magnetospheric field-aligned currents measured by Swarm satellites",
abstract = "Abstract The relationship between the magnetospheric field-aligned currents (FAC) monitored by the Swarm satellites and the magnetic activity PC index (which is a proxy of the solar wind energy incoming into the magnetosphere) is examined. It is shown that current intensities measured in the R1 and R2 FAC layers at the poleward and equtorward boundaries of the auroral oval are well correlated, the R2 currents being evidently secondary in relation to R1 currents and correlation in the dawn and dusk oval sectors being better than in the noon and night sectors. There is evident relationship between the PC index and the intensity of field-aligned currents in the R1 dawn and dusk layers: increase of FAC intensity in the course of substorm development is accompanied by increasing the PC index values. Correlation between PC and FAC intensities in the R2 dawn and dusk layers is also observed, but it is much weaker. No correlation is observed between PC and field-aligned currents in the midnight as well as in the noon sectors ahead of the substorm expansion phase. The results are indicative of the R1 field-aligned currents as a driver of the polar cap magnetic activity (PC index) and currents in the R2 layer.",
keywords = "Magnetospheric field-aligned currents, Auroral oval, PC index of magnetic activity, Magnetospheric substorms",
author = "О. Troshichev and D. Sormakov and R. Behlke",
year = "2018",
doi = "https://doi.org/10.1016/j.jastp.2017.12.020",
language = "English",
volume = "168",
pages = "37–47",
journal = "Journal of Atmospheric and Solar-Terrestrial Physics",
issn = "1364-6826",
publisher = "Elsevier",

}

Relationship between PC index and magnetospheric field-aligned currents measured by Swarm satellites. / Troshichev, О.; Sormakov, D.; Behlke, R.

In: Journal of Atmospheric and Solar-Terrestrial Physics, Vol. 168, 2018, p. 37–47.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - Relationship between PC index and magnetospheric field-aligned currents measured by Swarm satellites

AU - Troshichev, О.

AU - Sormakov, D.

AU - Behlke, R.

PY - 2018

Y1 - 2018

N2 - Abstract The relationship between the magnetospheric field-aligned currents (FAC) monitored by the Swarm satellites and the magnetic activity PC index (which is a proxy of the solar wind energy incoming into the magnetosphere) is examined. It is shown that current intensities measured in the R1 and R2 FAC layers at the poleward and equtorward boundaries of the auroral oval are well correlated, the R2 currents being evidently secondary in relation to R1 currents and correlation in the dawn and dusk oval sectors being better than in the noon and night sectors. There is evident relationship between the PC index and the intensity of field-aligned currents in the R1 dawn and dusk layers: increase of FAC intensity in the course of substorm development is accompanied by increasing the PC index values. Correlation between PC and FAC intensities in the R2 dawn and dusk layers is also observed, but it is much weaker. No correlation is observed between PC and field-aligned currents in the midnight as well as in the noon sectors ahead of the substorm expansion phase. The results are indicative of the R1 field-aligned currents as a driver of the polar cap magnetic activity (PC index) and currents in the R2 layer.

AB - Abstract The relationship between the magnetospheric field-aligned currents (FAC) monitored by the Swarm satellites and the magnetic activity PC index (which is a proxy of the solar wind energy incoming into the magnetosphere) is examined. It is shown that current intensities measured in the R1 and R2 FAC layers at the poleward and equtorward boundaries of the auroral oval are well correlated, the R2 currents being evidently secondary in relation to R1 currents and correlation in the dawn and dusk oval sectors being better than in the noon and night sectors. There is evident relationship between the PC index and the intensity of field-aligned currents in the R1 dawn and dusk layers: increase of FAC intensity in the course of substorm development is accompanied by increasing the PC index values. Correlation between PC and FAC intensities in the R2 dawn and dusk layers is also observed, but it is much weaker. No correlation is observed between PC and field-aligned currents in the midnight as well as in the noon sectors ahead of the substorm expansion phase. The results are indicative of the R1 field-aligned currents as a driver of the polar cap magnetic activity (PC index) and currents in the R2 layer.

KW - Magnetospheric field-aligned currents

KW - Auroral oval

KW - PC index of magnetic activity

KW - Magnetospheric substorms

U2 - https://doi.org/10.1016/j.jastp.2017.12.020

DO - https://doi.org/10.1016/j.jastp.2017.12.020

M3 - Journal article

VL - 168

SP - 37

EP - 47

JO - Journal of Atmospheric and Solar-Terrestrial Physics

JF - Journal of Atmospheric and Solar-Terrestrial Physics

SN - 1364-6826

ER -