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Title: Measurement of Large Parallel and Perpendicular Electric Fields on Electron Spatial Scales in the Terrestrial Bow Shock

Abstract

Large parallel ({<=}100 mV/m) and perpendicular ({<=}600 mV/m) electric fields were measured in the Earth's bow shock by the vector electric field experiment on the Polar satellite. These are the first reported direct measurements of parallel electric fields in a collisionless shock. These fields exist on spatial scales comparable to or less than the electron skin depth (a few kilometers) and correspond to magnetic-field-aligned potentials of tens of volts and perpendicular potentials up to a kilovolt. The perpendicular fields are amongst the largest ever measured in space, with energy densities of {epsilon}{sub 0}E{sup 2}/nk{sub B}T{sub e} of the order of 10%. The measured parallel electric field implies that the electrons are demagnetized, which may result in stochastic (rather than coherent) electron heating.

Authors:
;  [1]
  1. Physics Department and Space Sciences Laboratory, University of California, Berkeley, California 94720 (United States)
Publication Date:
OSTI Identifier:
20951376
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 20; Other Information: DOI: 10.1103/PhysRevLett.98.205001; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 58 GEOSCIENCES; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ELECTRIC FIELDS; ELECTRONS; ENERGY DENSITY; MAGNETIC FIELDS; POTENTIALS; SHOCK WAVES; STOCHASTIC PROCESSES; VECTORS

Citation Formats

Bale, S. D., and Mozer, F. S. Measurement of Large Parallel and Perpendicular Electric Fields on Electron Spatial Scales in the Terrestrial Bow Shock. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.205001.
Bale, S. D., & Mozer, F. S. Measurement of Large Parallel and Perpendicular Electric Fields on Electron Spatial Scales in the Terrestrial Bow Shock. United States. doi:10.1103/PHYSREVLETT.98.205001.
Bale, S. D., and Mozer, F. S. Fri . "Measurement of Large Parallel and Perpendicular Electric Fields on Electron Spatial Scales in the Terrestrial Bow Shock". United States. doi:10.1103/PHYSREVLETT.98.205001.
@article{osti_20951376,
title = {Measurement of Large Parallel and Perpendicular Electric Fields on Electron Spatial Scales in the Terrestrial Bow Shock},
author = {Bale, S. D. and Mozer, F. S.},
abstractNote = {Large parallel ({<=}100 mV/m) and perpendicular ({<=}600 mV/m) electric fields were measured in the Earth's bow shock by the vector electric field experiment on the Polar satellite. These are the first reported direct measurements of parallel electric fields in a collisionless shock. These fields exist on spatial scales comparable to or less than the electron skin depth (a few kilometers) and correspond to magnetic-field-aligned potentials of tens of volts and perpendicular potentials up to a kilovolt. The perpendicular fields are amongst the largest ever measured in space, with energy densities of {epsilon}{sub 0}E{sup 2}/nk{sub B}T{sub e} of the order of 10%. The measured parallel electric field implies that the electrons are demagnetized, which may result in stochastic (rather than coherent) electron heating.},
doi = {10.1103/PHYSREVLETT.98.205001},
journal = {Physical Review Letters},
number = 20,
volume = 98,
place = {United States},
year = {Fri May 18 00:00:00 EDT 2007},
month = {Fri May 18 00:00:00 EDT 2007}
}
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