ELFIN‐GPS Comparison of Energetic Electron Fluxes: Modeling Low‐Altitude Electron Flux Mapping to the Equatorial Magnetosphere
Abstract Near‐equatorial measurements of energetic electron fluxes, in combination with numerical simulation, are widely used for monitoring of the radiation belt dynamics. However, the long orbital periods of near‐equatorial spacecraft constrain the cadence of observations to once per several hours or greater, that is, much longer than the mesoscale injections and rapid local acceleration and losses of energetic electrons of interest. An alternative approach for radiation belt monitoring is to use measurements of low‐altitude spacecraft, which cover, once per hour or faster, the latitudinal range of the entire radiation belt within a few minutes. Such an approach requires, however, a procedure for mapping the flux from low equatorial pitch angles (near the loss cone) as measured at low altitude, to high equatorial pitch angles (far from the loss cone), as necessitated by equatorial flux models. Here we do this using the high energy resolution ELFIN measurements of energetic electrons. Combining those with GPS measurements we develop a model for the electron anisotropy coefficient, , that describes electron flux dependence on equatorial pitch‐angle, , . We then validate this model by comparing its equatorial predictions from ELFIN with in‐situ near‐equatorial measurements from Arase (ERG) in the outer radiation belt.
Authors
- Takefumi Mitani (ORCID: https://orcid.org/0000-0003-0492-3104)
- Iku Shinohara (ORCID: https://orcid.org/0000-0003-2700-0353)
- Kazuhiro Yamamoto (ORCID: https://orcid.org/0000-0002-2515-8643)
- Xiao‐Jia Zhang (ORCID: https://orcid.org/0000-0002-4185-5465)
- Shoichiro Yokota (ORCID: https://orcid.org/0000-0001-8851-9146)
- Weiqin Sun (ORCID: https://orcid.org/0000-0002-5568-3940)
- M. Teramoto (ORCID: https://orcid.org/0000-0001-5983-1149)
- Anton Artemyev (ORCID: https://orcid.org/0000-0001-8823-4474)
- D. Mourenas (ORCID: https://orcid.org/0000-0002-8413-6882)
- K. Keika (ORCID: https://orcid.org/0000-0003-0265-4318)
- Tomoaki Hori (ORCID: https://orcid.org/0000-0001-8451-6941)
- Ayako Matsuoka (ORCID: https://orcid.org/0000-0001-5777-9711)
- V. Angelopoulos (ORCID: https://orcid.org/0000-0001-7024-1561)
- Steven K. Morley (ORCID: https://orcid.org/0000-0001-8520-0199)
- Satoshi Kasahara (ORCID: https://orcid.org/0000-0002-3479-772X)
- Yoshizumi Miyoshi (ORCID: https://orcid.org/0000-0001-7998-1240)
- Takeshi Takashima (ORCID: https://orcid.org/0000-0002-7818-7800)
Institutions
- Planetary Science Institute (US)
- Los Alamos National Laboratory (US)
- University of California, Los Angeles (US)
- The University of Texas at Dallas (US)
- Kyushu Institute of Technology (JP)
- Kyoto University (JP)
- Commissariat à l'Énergie Atomique et aux Énergies Alternatives (FR)
- Université Paris-Saclay (FR)
- Japan Aerospace Exploration Agency (JP)
- CEA DAM Île-de-France (FR)
- CEA Paris-Saclay (FR)
- Institute of Space and Astronautical Science (JP)
- Nagoya University (JP)
- The University of Tokyo (JP)
Publication Details
- Journal
- Journal of Geophysical Research Space Physics
- Published
- 2024-10-28
- DOI
- https://doi.org/10.1029/2024ja033155
- Citations
- 3
- Primary Topic
- Ionosphere and magnetosphere dynamics
- Type
- article
- Field-Weighted Citation Impact
- 0.99
Funders
- National Science Foundation
- National Aeronautics and Space Administration