Leakage ions from the LLBL to MSBL: Confirmation of reconnection events at the dayside magnetopause

M. Nakamura, T. Terasawa, H. Kawano, M. Fujimoto, M. Hirahara, T. Mukai, S. Machida, Y. Saito, S. Kokubun, T. Yamamoto, K. Tsuruda

Research output: Contribution to journalArticle

6 Citations (Scopus)


This letter reports on leakage ions from the low latitude boundary layer (LLBL) to the magnetosheath boundary layer (MSBL) as observed by Geotail at the dayside magnetopause. A reconnection of the interplanetary magnetic field (IMF) with magnetospheric field lines is shown to be responsible for the leakage. Based on analysis of a variation in lower cut-off levels occurring in the velocity distribution function of the leakage ions, we propose a "velocity filter effect" model with a finite source region to explain this variation. The location of the reconnection region is subsequently calculated to be 2.2RE north of the geomagnetic equatorial plane under the proposed velocity filter effect model.

Original languageEnglish
Pages (from-to)65-70
Number of pages6
JournalJournal of geomagnetism and geoelectricity
Issue number1
Publication statusPublished - Jan 1 1996
Externally publishedYes


All Science Journal Classification (ASJC) codes

  • Environmental Science(all)
  • Earth and Planetary Sciences(all)

Cite this