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Title: Energetic electron acceleration observed by MMS in the vicinity of an X-line crossing

Abstract

During the first months of observations, the Magnetospheric Multiscale Fly's Eye Energetic Particle Spectrometer instrument has observed several instances of electron acceleration up to >100 keV while in the vicinity of the dayside reconnection region. While particle acceleration associated with magnetic reconnection has been seen to occur up to these energies in the tail region, it had not yet been reported at the magnetopause. This study reports on observations of electron acceleration up to hundreds of keV that were recorded on 19 September 2015 around 1000 UT, in the midst of an X-line crossing. In the region surrounding the X-line, whistler-mode and broadband electrostatic waves were observed simultaneously with the appearance of highly energetic electrons which exhibited significant energization in the perpendicular direction. The mechanisms by which particles may be accelerated via reconnection-related processes are intrinsic to understanding particle dynamics among a wide range of spatial scales and plasma environments.

Authors:
 [1];  [2];  [1];  [3];  [1];  [2];  [2];  [4];  [4]; ORCiD logo [5];  [1];  [6];  [6];  [7];  [8]
  1. Univ. of Colorado, Boulder, CO (United States)
  2. The Aerospace Corporation, El Segundo, CA (United States)
  3. Aalto Univ., Otaniemi (Finland)
  4. The Johns Hopkins University Applied Physics Lab., Laurel, MD (United States)
  5. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  6. NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States)
  7. Univ. of New Hampshire, Durham, NH (United States)
  8. Southwest Research Inst. (SwRI), San Antonio, TX (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:
1402635
Report Number(s):
LA-UR-17-24824
Journal ID: ISSN 0094-8276; TRN: US1702885
Grant/Contract Number:
AC52-06NA25396
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Geophysical Research Letters
Additional Journal Information:
Journal Volume: 43; Journal Issue: 14; Journal ID: ISSN 0094-8276
Publisher:
American Geophysical Union
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; Heliospheric and Magnetospheric Physics

Citation Formats

Jaynes, A. N., Turner, D. L., Wilder, F. D., Osmane, A., Baker, D. N., Blake, J. B., Fennell, J. F., Cohen, I. J., Mauk, B. H., Reeves, G. D., Ergun, R. E., Giles, B. L., Gershman, D. J., Torbert, R. B., and Burch, J. L. Energetic electron acceleration observed by MMS in the vicinity of an X-line crossing. United States: N. p., 2016. Web. doi:10.1002/2016GL069206.
Jaynes, A. N., Turner, D. L., Wilder, F. D., Osmane, A., Baker, D. N., Blake, J. B., Fennell, J. F., Cohen, I. J., Mauk, B. H., Reeves, G. D., Ergun, R. E., Giles, B. L., Gershman, D. J., Torbert, R. B., & Burch, J. L. Energetic electron acceleration observed by MMS in the vicinity of an X-line crossing. United States. doi:10.1002/2016GL069206.
Jaynes, A. N., Turner, D. L., Wilder, F. D., Osmane, A., Baker, D. N., Blake, J. B., Fennell, J. F., Cohen, I. J., Mauk, B. H., Reeves, G. D., Ergun, R. E., Giles, B. L., Gershman, D. J., Torbert, R. B., and Burch, J. L. 2016. "Energetic electron acceleration observed by MMS in the vicinity of an X-line crossing". United States. doi:10.1002/2016GL069206. https://www.osti.gov/servlets/purl/1402635.
@article{osti_1402635,
title = {Energetic electron acceleration observed by MMS in the vicinity of an X-line crossing},
author = {Jaynes, A. N. and Turner, D. L. and Wilder, F. D. and Osmane, A. and Baker, D. N. and Blake, J. B. and Fennell, J. F. and Cohen, I. J. and Mauk, B. H. and Reeves, G. D. and Ergun, R. E. and Giles, B. L. and Gershman, D. J. and Torbert, R. B. and Burch, J. L.},
abstractNote = {During the first months of observations, the Magnetospheric Multiscale Fly's Eye Energetic Particle Spectrometer instrument has observed several instances of electron acceleration up to >100 keV while in the vicinity of the dayside reconnection region. While particle acceleration associated with magnetic reconnection has been seen to occur up to these energies in the tail region, it had not yet been reported at the magnetopause. This study reports on observations of electron acceleration up to hundreds of keV that were recorded on 19 September 2015 around 1000 UT, in the midst of an X-line crossing. In the region surrounding the X-line, whistler-mode and broadband electrostatic waves were observed simultaneously with the appearance of highly energetic electrons which exhibited significant energization in the perpendicular direction. The mechanisms by which particles may be accelerated via reconnection-related processes are intrinsic to understanding particle dynamics among a wide range of spatial scales and plasma environments.},
doi = {10.1002/2016GL069206},
journal = {Geophysical Research Letters},
number = 14,
volume = 43,
place = {United States},
year = 2016,
month = 7
}

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