Altitude variation of the plasmapause signature in the main ionospheric trough |
| |
| Authors: | Joseph M. Grebowsky Robert F. Benson Phillip A. Webb Vladimir Truhlik Dieter Bilitza |
| |
| Affiliation: | 1. Planetary Magnetospheres Laboratory, Code 695, Solar System Exploration Division, Goddard Space Flight Center, Greenbelt, MD 20771, USA;2. Geospace Physics Laboratory, Code 673, Heliophysics Science Division, Goddard Space Flight Center, Greenbelt, MD 20771, USA;3. GEST/UMBC/Space Weather Laboratory, Code 674, Heliophysics Science Division, Goddard Space Flight Center, Greenbelt, MD 20771 USA;4. Institute of Atmospheric Physics, Academy of Science Czech Republic, Praha, Czech Republic;5. GMU/Heliospheric Physics Laboratory, Code 672, Heliophysics Science Division, Goddard Space Flight Center, Greenbelt, MD 20771, USA;1. Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Rd., Laurel, MD 20723, USA;2. Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Rd., Laurel, MD 20723, USA;3. Airforce Research Laboratory, Space Vehicles Directorate, Hanscom Air Force Base, Massachusetts, USA;4. Department of Atmospheric and Oceanic Sciences, University of California, Los Ageles, California, USA;5. Space Science Department, National Space Science and Technology Center, NASA Marshall Space Flight Center, Huntsville, Alabama, USA;1. Institute of Atmospheric Physics, Academy of Sciences of the Czech Republic, Bocni II, 14131 Prague, Czech Republic;2. George Mason University, School of Physics, Astronomy and Computational Science, 4400 University Drive, Fairfax, VA 22030, USA;3. NASA Goddard Space Flight Center, Heliospheric Physics Laboratory, Greenbelt, MD 20771, USA;1. Physics Department, Regis University, 3333 Regis Blvd, Denver, CO 80221, USA;2. High Altitude Observatory, National Center for Atmospheric Research, 3080 Center Green Dr., Boulder, CO 80301, USA;3. Dept. Applied Mathematics, Univ. of Colorado, Boulder, CO 80309, USA;1. Astronomical Observatory Zagreb, Croatia;2. Faculty of Science, University of Zagreb, Croatia;3. Royal Belgian Institute for Space Aeronomy (Space Physics and STCE), Brussels, Belgium;4. Earth and Life Institute, TECLIM, Université Catholique de Louvain, Louvain-La-Neuve, Belgium;5. Department of Astronomy and Space Science, Chungbuk National University, Cheongju-si, South Korea;1. Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, Telegrafenberg, 14473 Potsdam, Germany;2. Department of Space Physics, College of Electronic Information, Wuhan University, 430079 Wuhan, China;3. Copernicus Gesellschaft e.V., 37081 Göttingen, Germany;1. Department of Physics, University of Lagos, Akoka, Yaba, Lagos, Nigeria;2. Institute of Maritime Studies, University of Lagos, Akoka, Yaba, Lagos, Nigeria;3. Comm., Navig. and Surveillance Directorate, Nigerian Civil Aviation Authority, Ikeja, Lagos, Nigeria;4. Institute for Scientific Research, Boston College, Chestnut Hill, MA 02467, USA |
| |
| Abstract: | The projection of the plasmapause magnetic-field lines to low altitudes, where the light-ion chemistry is dominated by O+, tends to occur near the minimum electron density in the main (midlatitude) electron density trough at night. With increasing altitude in the trough, where H+ emerges as the dominant ion on the low-latitude boundary, we have found cases where the plasmapause field lines are located on the sharp low-latitude side of the trough as expected if this topside ionosphere H+ distribution varies in step with the plasmapause gradient in the distant plasmasphere. These conclusions are based on near-equatorial crossings of the plasmapause (corresponding to the steep gradient in the dominant species H+) by the Explorer-45 satellite as determined from electric-field measurements by Maynard and Cauffman in the early 1970s and ISIS-2 ionospheric topside-sounder measurements. The former data have now been converted to digital form and made available at http://nssdcftp.gsfc.nasa.gov. The latter provide samples of nearly coincident observations of ionospheric main trough crossings near the same magnetic-field lines of the Explorer 45-determined equatorial plasmapause. The ISIS-2 vertical electron density profiles are used to infer where the F-region transitions from an O+ to a H+ dominated plasma through the main trough boundaries. |
| |
| Keywords: | Plasmapause Ionosphere Midlatitude Trough |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
