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A Pi2-associated dusk-to-dawn currents in the midnight sector as observed at L = 6.6 during multiple Pi2 onsets

Earth, Planets and Space volume 56, pages 663–668 (2004)Cite this article

Abstract

We examined the magnetic fields and energetic particle data from geosynchronous satellites GOES 6 and S/C1984-129 during the multiple onset of Pi2. We found that the energetic particle injection in the midnight sector was associated with the consecutive Pi2 onset. The magnetometer on board GOES 6 at the midnight sector detected the increase of the field inclination as well as a decrease of the field magnitudes during the Pi2 events. We suggest that such a field reconfiguration could be provoked by the formation of the dusk-to-dawn currents in the vicinity of the geosynchronous altitudes. The present study supports the Pi2 model that the impulsive dusk-to-dawn current and field-aligned current diverted from it are a source of Pi2 pulsation in the midnight magnetosphere.

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Authors and Affiliations

  1. Department of Physics, Kurume National College of Technology, Kurume, 830-8555, Japan

    O. Saka

  2. Department of Earth and Planetary Science, Kyushu University, Fukuoka, 812-8581, Japan

    H. Akaki

  3. Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO, 80309, USA

    D. N. Baker

Authors
  1. O. Saka
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  2. H. Akaki
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  3. D. N. Baker
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Correspondence to O. Saka.

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Saka, O., Akaki, H. & Baker, D.N. A Pi2-associated dusk-to-dawn currents in the midnight sector as observed at L = 6.6 during multiple Pi2 onsets. Earth Planet Sp 56, 663–668 (2004). https://doi.org/10.1186/BF03352528

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  • DOI: https://doi.org/10.1186/BF03352528

Key words

  • Magnetospheric substorm
  • Pi2 onset
  • plasma dynamics
  • geosynchronous altitudes