NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Quantified Energy Dissipation Rates in the Terrestrial Bow ShockWe present the first quantified measure of the energy dissipation rates, due to wave-particle interactions, in the transition region of the Earth's collision-less bow shock using data from the Time History of Events and Macro-Scale Interactions during Sub-Storms spacecraft. Our results show that wave-particle interactions can regulate the global structure and dominate the energy dissipation of collision-less shocks. In every bow shock crossing examined, we observed both low-frequency (less than 10 hertz) and high-frequency (approximately or greater than10 hertz) electromagnetic waves throughout the entire transition region and into the magnetosheath. The low-frequency waves were consistent with magnetosonic-whistler waves. The high-frequency waves were combinations of ion-acoustic waves, electron cyclotron drift instability driven waves, electrostatic solitary waves, and whistler mode waves. The high-frequency waves had the following: (1) peak amplitudes exceeding delta B approximately equal to 10 nanoteslas and delta E approximately equal to 300 millivolts per meter, though more typical values were delta B approximately equal to 0.1-1.0 nanoteslas and delta E approximately equal to 10-50 millivolts per meter (2) Poynting fluxes in excess of 2000 microWm(sup −2) (micro-waves per square meter) (typical values were approximately 1-10 microWm(sup −2) (micro-waves per square meter); (3) resistivities greater than 9000 omega meters; and (4) associated energy dissipation rates greater than 10 microWm(sup −3) (micro-waves per cubic meter). The dissipation rates due to wave-particle interactions exceeded rates necessary to explain the increase in entropy across the shock ramps for approximately 90 percent of the wave burst durations. For approximately 22 percent of these times, the wave-particle interactions needed to only be less than or equal to 0.1 percent efficient to balance the nonlinear wave steepening that produced the shock waves. These results show that wave-particle interactions have the capacity to regulate the global structure and dominate the energy dissipation of collision-less shocks.
Document ID
20160005863
Acquisition Source
Goddard Space Flight Center
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Wilson, L. B., III
(NASA Goddard Space Flight Center Greenbelt, MD United States)
Sibeck, D. G.
(NASA Goddard Space Flight Center Greenbelt, MD United States)
Breneman, A. W.
(Minnesota Univ. Minneapolis, MN, United States)
Le Contel, O.
(Ecole Polytechnique Palaiseau, France)
Cully, C.
(Calgary Univ. Alberta, Canada)
Turner, D. L.
(California Univ. Los Angeles, CA, United States)
Angelopoulos, V.
(California Univ. Los Angeles, CA, United States)
Malaspina, D. M.
(Colorado Univ. Boulder, CO, United States)
Date Acquired
May 5, 2016
Publication Date
August 25, 2014
Publication Information
Publication: Journal of Geophysical Research: Space Physics
Publisher: AGU Publications
Volume: 119
Issue: 8
e-ISSN: 2169-9402
Subject Category
Geophysics
Report/Patent Number
GSFC-E-DAA-TN31887
Distribution Limits
Public
Copyright
Other
Keywords
Terrestrial bow 2

Available Downloads

There are no available downloads for this record.
No Preview Available