Locations of proton isotropic boundaries as measured by conjugate high-altitude and low-altitude satellites

NY Ganushkina*, Tommi Karhunen, MV Kubyshkina, Y Ebihara, VA Sergeev, TI Pulkkinen, TA Fritz

*Corresponding author for this work

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Abstract

Polar CAMMICE MICS data of proton pitch angle distributions with energies of 31-80 keV for the period of 1997-1998 were analyzed to determine the locations where anisotropic pitch angle distributions (perpendicular flux dominating) change to isotropic distributions. We study this high-altitude isotropic distribution boundary (IDB) in terms of its location in L-shell and MLT. Statistical results showed that this boundary is located at lower L-shells on the nightside and at higher L-shells on the dayside with most distant location at dawn. With the increase of magnetic activity, the IDB positions shift towards lower L-shells at all MLT. The locations of IDBs were also determined for different storm phases. A superposed epoch analysis revealed that the L-shells of the IDBs move to lower L-shells with decreasing Dst and to higher L-shells during Dst recovery. We made a comparison between Polar measurements of IDB at high altitudes and DMSP measurements of b2i boundary at low altitudes selecting several events during which simultaneous observations in the same local time sector were available. The magnetic field mapping using the Tsyganenko T01 model with the observed solar wind input parameters showed that Polar and DMSP were placed on nearly the same field lines, which leads us to suggest that the Polar IDI3 and the b2i boundary at DMSP are related. (C) 2003 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

Original languageEnglish
Title of host publicationPLASMA PROCESSES IN THE NEAR-EARTH SPACE: INTERBALL AND BEYOND
EditorsDG Sibeck, GN Zastenker
Pages1265-1270
Number of pages6
DOIs
Publication statusPublished - 2003
MoE publication typeA4 Article in a conference publication
EventCOSPAR Colloquium on Plasma Processes in the Near-Earth Space - Sofia, Bulgaria
Duration: 5 Feb 200210 Feb 2002

Publication series

NameADVANCES IN SPACE RESEARCH
PublisherPERGAMON-ELSEVIER SCIENCE LTD
Volume31
ISSN (Print)0273-1177

Conference

ConferenceCOSPAR Colloquium on Plasma Processes in the Near-Earth Space
CountryBulgaria
CitySofia
Period05/02/200210/02/2002

Keywords

  • PRECIPITATION
  • MAGNETOSPHERE
  • CONFIGURATION
  • MAGNETOTAIL
  • MIDNIGHT
  • STATE

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