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Title: Self-consistent modeling of electron precipitation and responses in the ionosphere: application to low-altitude energization during substorms

Here, we report a new modeling capability that self–consistently couples physics–based magnetospheric electron precipitation with its impact on the ionosphere. Specifically, the ring current model RAM–SCBE is two–way coupled to an ionospheric electron transport model GLOW, representing a significant improvement over previous models, in which the ionosphere is either treated as a 2D spherical boundary of the magnetosphere, or is driven by empirical precipitation models that are incapable of capturing small–scale, transient variations. The new model enables us to study the impact of substorm–associated, spectrum–resolved electron precipitation on the 3D ionosphere. We found that after each substorm injection, a high–energy tail of precipitation is produced in the dawn sector outside the plasmapause, by energetic electrons (10 < E < 100 keV) scattered by whistler–mode chorus waves. Consequently, an ionospheric sub–layer characterized by enhanced Pedersen conductivity arises at unusually low altitude (~85 km), with its latitudinal width of ~5–10° in the auroral zone. The sub–layer structure appears intermittently, in correlation with recurrent substorm injections. It propagates eastward from the nightside to the dayside in the same drift direction of source electrons injected from the plasmasheet, resulting in global impact within the ionosphere. In conclusion, this study demonstrates the model's capability ofmore » revealing complex cross–scale interactions in the geospace environment.« less
Authors:
ORCiD logo [1] ; ORCiD logo [2] ; ORCiD logo [3] ; ORCiD logo [4]
  1. Beihang Univ., Beijing (China)
  2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  3. Univ. Corp. for Atmospheric Research, Boulder, CO (United States); California Inst. of Technology (CalTech), Pasadena, CA (United States)
  4. National Center for Atmospheric Research, Boulder, CO (United States)
Publication Date:
Report Number(s):
LA-UR-18-21528
Journal ID: ISSN 0094-8276
Grant/Contract Number:
AC52-06NA25396; DEAC52-06NA25396
Type:
Accepted Manuscript
Journal Name:
Geophysical Research Letters
Additional Journal Information:
Journal Name: Geophysical Research Letters; Journal ID: ISSN 0094-8276
Publisher:
American Geophysical Union
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
USDOE Laboratory Directed Research and Development (LDRD) Program
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; Heliospheric and Magnetospheric Physics; self-consistent MI coupling; electron precipitation; conductivity sub-layer; high-energy tail precipitation; low-altitude ionization
OSTI Identifier:
1458960
Alternate Identifier(s):
OSTI ID: 1460037