Intense energetic electron flux enhancements in Mercury's magnetosphere: An integrated view with high-resolution observations from MESSENGER.
The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission to Mercury has provided a wealth of new data about energetic particle phenomena. With observations from MESSENGER's Energetic Particle Spectrometer, as well as data arising from energetic electrons recorded by the X-Ray Spectrometer and Gamma-Ray and Neutron Spectrometer (GRNS) instruments, recent work greatly extends our record of the acceleration, transport, and loss of energetic electrons at Mercury. The combined data sets include measurements from a few keV up to several hundred keV in electron kinetic energy and have permitted relatively good spatial and temporal resolution for many events. We focus here on the detailed nature of energetic electron bursts measured by the GRNS system, and we place these events in the context of solar wind and magnetospheric forcing at Mercury. Our examination of data at high temporal resolution (10 ms) during the period March 2013 through October 2014 supports strongly the view that energetic electrons are accelerated in the near-tail region of Mercury's magnetosphere and are subsequently "injected" onto closed magnetic field lines on the planetary nightside. The electrons populate the plasma sheet and drift rapidly eastward toward the dawn and prenoon sectors, at times executing multiple complete drifts around the planet to form "quasi-trapped" populations.
Laboratory for Atmospheric and Space Physics University of Colorado Boulder Colorado USA.
Daniel N
DN
Baker
Laboratory for Atmospheric and Space Physics University of Colorado Boulder Colorado USA.
Ryan M
RM
Dewey
The Johns Hopkins University Applied Physics Laboratory Laurel Maryland USA.
David J
DJ
Lawrence
The Johns Hopkins University Applied Physics Laboratory Laurel Maryland USA.
John O
JO
Goldsten
The Johns Hopkins University Applied Physics Laboratory Laurel Maryland USA.
Patrick N
PN
Peplowski
The Johns Hopkins University Applied Physics Laboratory Laurel Maryland USA.
Haje
H
Korth
Department of Atmospheric, Oceanic and Space Sciences University of Michigan Ann Arbor Michigan USA.
James A
JA
Slavin
The Johns Hopkins University Applied Physics Laboratory Laurel Maryland USA; Office of Space Research and Technology Academy of Athens Athens Greece.
Stamatios M
SM
Krimigis
The Johns Hopkins University Applied Physics Laboratory Laurel Maryland USA.
Brian J
BJ
Anderson
The Johns Hopkins University Applied Physics Laboratory Laurel Maryland USA.
George C
GC
Ho
The Johns Hopkins University Applied Physics Laboratory Laurel Maryland USA.
Ralph L
RL
McNutt
Department of Atmospheric, Oceanic and Space Sciences University of Michigan Ann Arbor Michigan USA.
Jim M
JM
Raines
Department of Physics and Astronomy University of California Los Angeles California USA.
David
D
Schriver
Department of Terrestrial Magnetism Carnegie Institution of Washington Washington District of Columbia USA; Lamont-Doherty Earth Observatory Columbia University Palisades New York USA.
Sean C
SC
Solomon
Mercury magnetosphere; electron acceleration; particle bursts; substorms