On the Dynamical Development of the Downward Field-Aligned Current in the Substorm Current Wedge

RJ PELLINEN*, T.I. Pulkkinen, A HUUSKONEN, KH GLASSMEIER

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

Abstract

Data from the Scandinavian magnetometer array, a multichannel scanning photometer, and all-sky cameras have been combined to study the carriers of the downward field-aligned current in the substorm current wedge during the first minutes after the substorm onset. The ions are slow and thus cannot contribute much to the downward current immediately after the substorm onset, whereas the precipitating magnetospheric electrons can quickly set up the upward current. On March 4, 1979, magnetometers and all-sky cameras recorded a substorm onset at similar to 2236 UT slightly to the west of the stations. A scanning photometer was located at the center of the downward current during the event. The observations suggest that the downward current in this event was set up less than a minute after the formation of the upward current and that at this stage the current was mainly carried by cold ionospheric electrons.

Original languageEnglish
Pages (from-to)14863-14873
Number of pages11
JournalJournal of Geophysical Research
Volume100
Issue numberA8
DOIs
Publication statusPublished - 1 Aug 1995
MoE publication typeA1 Journal article-refereed

Keywords

  • GROUND-BASED OBSERVATIONS
  • AURORAL-ZONE
  • MAGNETOMETER ARRAY
  • ELECTRIC-FIELDS
  • MAGNETOTAIL
  • MAGNETOSPHERE
  • PHASE
  • IMS

Cite this