Journal metrics

Journal metrics

  • IF value: 1.621 IF 1.621
  • IF 5-year value: 1.614 IF 5-year 1.614
  • CiteScore value: 1.61 CiteScore 1.61
  • SNIP value: 0.900 SNIP 0.900
  • SJR value: 0.910 SJR 0.910
  • IPP value: 1.58 IPP 1.58
  • h5-index value: 24 h5-index 24
  • Scimago H index value: 80 Scimago H index 80
Discussion papers | Copyright
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.

Regular paper 25 Jun 2018

Regular paper | 25 Jun 2018

Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Annales Geophysicae (ANGEO).

Dynamics Geomagnetic Storm on 7–10 September 2015 as Observed by TWINS and Simulated by CIMI

Joseph D. Perez1, James Edmond1, Shannon Hill2, Hanyun Xu1, Natalia Buzulukova3, Mei-Ching Fok3, Jerry Goldstein4,5, David J. McComas6, and Phil Valek4,5 Joseph D. Perez et al.
  • 1Auburn University, Auburn, AL 36849, USA
  • 2Emory University, Atlanta, GA 30322, USA
  • 3NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
  • 4Southwest Research Institute, San Antonio, TX 78228, USA
  • 5University of Texas at San Antonio, TX 78249, USA
  • 6Department of Astrophysical Sciences, Princeton University, NJ 08540, USA

Abstract. For the first time, direct comparisons of the equatorial ion pressure and pitch angle anisotropy observed by TWINS and simulated by CIMI are presented. The TWINS ENA images are from a 4-day period, 7–10 September 2015. The simulations use both the empirical Weimer 2K and the self-consistent RCM electric potentials. There are two moderate storms in succession during this period. In most cases, we find that the general features of the ring current in the inner magnetosphere obtained from the observations and the simulations are similar. Nevertheless, we do see consistent indications of enhanced electric and magnetic shielding in the TWINS observations. The simulated pressure peaks are often inside the observed peaks and more toward dusk than the measured values. There are also cases in which the measured equatorial ion pressure shows multiple peaks that are not seen in the simulations. This occurs during a period of intense AE index, suggesting time and spatially dependent injections from the plasma sheet that are not included in these simulations. The simulations consistently show regions of parallel anisotropy spanning the night side between approximately 6 and 8 RE whereas the parallel anisotropy is seen in the observations only during the main phase of the first storm. This may indicate stronger electric and magnetic shielding than is present in the simulations. The evidence form the unique global view provided by the TWIN observations strongly suggests that there are features in the ring current pressure distributions that can be best explained by enhanced electric and magnetic shielding and/or spatially-localized, short-duration injections..

Download & links
Joseph D. Perez et al.
Interactive discussion
Status: final response (author comments only)
Status: final response (author comments only)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Login for Authors/Topical Editors] [Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement
Joseph D. Perez et al.
Joseph D. Perez et al.
Total article views: 326 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
269 52 5 326 3 3
  • HTML: 269
  • PDF: 52
  • XML: 5
  • Total: 326
  • BibTeX: 3
  • EndNote: 3
Views and downloads (calculated since 25 Jun 2018)
Cumulative views and downloads (calculated since 25 Jun 2018)
Viewed (geographical distribution)
Total article views: 326 (including HTML, PDF, and XML) Thereof 325 with geography defined and 1 with unknown origin.
Country # Views %
  • 1
No saved metrics found.
No discussed metrics found.
Latest update: 17 Sep 2018
Publications Copernicus
Short summary
Pressure and anisotropy profiles from trapped ions in the ring current as observed from energetic neutral atom images are compared to numerical simulations for the first time. The results show evidence for short time and spatially localized injections from the plasma sheet.
Pressure and anisotropy profiles from trapped ions in the ring current as observed from...