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Title: Microinjections observed by MMS FEEPS in the dusk to midnight region

Energetic electron injections are commonly observed in the premidnight to dawn regions in association with substorms. However, successive electron injections are generally separated in time by hours and are rarer in the dusk region of the inner magnetosphere. Early MMS energetic electron data taken in the dusk to premidnight regions above ~9 RE show many clusters of electron injections. These injections of 50–400 keV electrons have energy dispersion signatures indicating that they gradient and curvature drifted from earlier local times. We focus on burst rate data starting near 21:00 UT on 6 August 2015. A cluster of ~40 electron injections occurred in the following 4 h interval. The highest-resolution data showed that the electrons in the injections were trapped and had bidirectional field-aligned angular distributions. Here, these injection clusters are a new phenomenon in this region of the magnetosphere.
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  1. The Aerospace Corporation, El Segundo, CA (United States)
  2. The Johns Hopkins Univ. Applied Physics Lab., Laurel, MD (United States)
  3. Univ. of Colorado, Boulder, CO (United States)
  4. Univ. of New Hampshire, Durham, NH (United States)
  5. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  6. Southwest Research Institute, San Antonio, TX (United States)
  7. Goddard Spaceflight Center, College Park, MD (United States)
  8. Goddard Spaceflight Center, College Park, MD (United States); NASA Headquarters, Washington, D.C. (United States)
  9. Univ. of California, Los Angeles, CA (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 0094-8276; TRN: US1702892
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Geophysical Research Letters
Additional Journal Information:
Journal Volume: 43; Journal Issue: 12; Journal ID: ISSN 0094-8276
American Geophysical Union
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
National Aeronautic and Space Administration (NASA); USDOE
Country of Publication:
United States
58 GEOSCIENCES; Heliospheric and Magnetospheric Physics; electron microinjections; electron energization; duskside plasma sheet; MMS
OSTI Identifier: