Reformulation and energy flow of the Cowling channel

R. Fujii, O. Amm, A. Yoshikawa, A. Ieda, H. Vanhamäki

Research output: Contribution to journalArticle

27 Citations (Scopus)

Abstract

The question to which extent the divergence of the Hall current can be connected to the Pedersen current or to the closure current in the magnetosphere through field-aligned currents (FACs), that is, the Cowling channel process in the polar region, has long been debated but not fully understood. The present study reformulates the Cowling channel by introducing a two-layer model consisting of Hall and Pedersen conductivity layers with channel boundaries not only in the direction perpendicular to the channel but also in the direction along it. This new model enables us to better and more physically understand the connection between the Hall current, Pedersen current, and FAC. In particular, the finiteness of the channel along its direction enables us to understand that the primary nonzero electric field along the channel and FACs at the channel boundaries that faced each other in the channel direction carries the necessary energy for the Hall current to set up the secondary electric field from the magnetosphere. A case for a possible connection between the Pedersen and Hall currents is shown based on a polar current system derived from the Kamide-Richmond-Matsushita method. A more comprehensive analysis based on data is presented in the companion paper.

Original languageEnglish
Article numberA02305
JournalJournal of Geophysical Research: Space Physics
Volume116
Issue number2
DOIs
Publication statusPublished - Jan 1 2011

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cowlings
Magnetosphere
energy flow
Electric fields
electric field
Hall currents
Pedersen currents
field aligned currents
Polar Regions
energy
magnetospheres
magnetosphere
electric fields
Direction compound
polar region
polar regions
closures
divergence
conductivity
methodology

All Science Journal Classification (ASJC) codes

  • Geophysics
  • Forestry
  • Oceanography
  • Aquatic Science
  • Ecology
  • Water Science and Technology
  • Soil Science
  • Geochemistry and Petrology
  • Earth-Surface Processes
  • Atmospheric Science
  • Earth and Planetary Sciences (miscellaneous)
  • Space and Planetary Science
  • Palaeontology

Cite this

Reformulation and energy flow of the Cowling channel. / Fujii, R.; Amm, O.; Yoshikawa, A.; Ieda, A.; Vanhamäki, H.

In: Journal of Geophysical Research: Space Physics, Vol. 116, No. 2, A02305, 01.01.2011.

Research output: Contribution to journalArticle

Fujii, R. ; Amm, O. ; Yoshikawa, A. ; Ieda, A. ; Vanhamäki, H. / Reformulation and energy flow of the Cowling channel. In: Journal of Geophysical Research: Space Physics. 2011 ; Vol. 116, No. 2.
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