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

Abstract

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.

Authors:
 [1];  [1];  [1];  [1];  [1];  [2];  [3];  [2];  [2];  [3];  [3];  [4]; ORCiD logo [5];  [4];  [6];  [7];  [8];  [9]
  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:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
National Aeronautic and Space Administration (NASA); USDOE
OSTI Identifier:
1402658
Report Number(s):
LA-UR-17-28043
Journal ID: ISSN 0094-8276; TRN: US1702892
Grant/Contract Number:
AC52-06NA25396
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Geophysical Research Letters
Additional Journal Information:
Journal Volume: 43; Journal Issue: 12; Journal ID: ISSN 0094-8276
Publisher:
American Geophysical Union
Country of Publication:
United States
Language:
English
Subject:
58 GEOSCIENCES; Heliospheric and Magnetospheric Physics; electron microinjections; electron energization; duskside plasma sheet; MMS

Citation Formats

Fennell, Joseph F., Turner, D. L., Lemon, C. L., Blake, J. B., Clemmons, J. H., Mauk, B. H., Jaynes, A. N., Cohen, I. J., Westlake, J. H., Baker, D. N., Craft, J. V., Spence, H. E., Reeves, Geoffrey D., Torbert, R. B., Burch, J. L., Giles, B. L., Paterson, W. R., and Strangeway, R. J.. Microinjections observed by MMS FEEPS in the dusk to midnight region. United States: N. p., 2016. Web. doi:10.1002/2016GL069207.
Fennell, Joseph F., Turner, D. L., Lemon, C. L., Blake, J. B., Clemmons, J. H., Mauk, B. H., Jaynes, A. N., Cohen, I. J., Westlake, J. H., Baker, D. N., Craft, J. V., Spence, H. E., Reeves, Geoffrey D., Torbert, R. B., Burch, J. L., Giles, B. L., Paterson, W. R., & Strangeway, R. J.. Microinjections observed by MMS FEEPS in the dusk to midnight region. United States. doi:10.1002/2016GL069207.
Fennell, Joseph F., Turner, D. L., Lemon, C. L., Blake, J. B., Clemmons, J. H., Mauk, B. H., Jaynes, A. N., Cohen, I. J., Westlake, J. H., Baker, D. N., Craft, J. V., Spence, H. E., Reeves, Geoffrey D., Torbert, R. B., Burch, J. L., Giles, B. L., Paterson, W. R., and Strangeway, R. J.. 2016. "Microinjections observed by MMS FEEPS in the dusk to midnight region". United States. doi:10.1002/2016GL069207. https://www.osti.gov/servlets/purl/1402658.
@article{osti_1402658,
title = {Microinjections observed by MMS FEEPS in the dusk to midnight region},
author = {Fennell, Joseph F. and Turner, D. L. and Lemon, C. L. and Blake, J. B. and Clemmons, J. H. and Mauk, B. H. and Jaynes, A. N. and Cohen, I. J. and Westlake, J. H. and Baker, D. N. and Craft, J. V. and Spence, H. E. and Reeves, Geoffrey D. and Torbert, R. B. and Burch, J. L. and Giles, B. L. and Paterson, W. R. and Strangeway, R. J.},
abstractNote = {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.},
doi = {10.1002/2016GL069207},
journal = {Geophysical Research Letters},
number = 12,
volume = 43,
place = {United States},
year = 2016,
month = 6
}

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