NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Correlated low-frequency electric and magnetic noise along the auroral field linesDynamics Explorer 1 measurements of intense low-frequency electric and magnetic noise observed at low altitudes over the auroral zone are described. The intensity of both the electric and magnetic fields decreases rapidly with increasing frequency. Most of the energy is at frequencies below the O(+) cyclotron frequency, and some evidence is found for a cutoff or change in spectral slope near that frequency. The magnetic to electric field ratio decreases rapidly with increasing radial distance and also decreases with increasing frequency. The polarization of the electric field in a plane perpendicular to the earth's magnetic field is essentially random. The transverse electric and magnetic fields are closely correlated, with the average Poynting flux directed toward the earth. The total electromagnetic power flow associated with the noise is substantial. Two general models are discussed to interpret these observations, one based on static electric and magnetic fields imbedded in the ionosphere and the other based on Alfven waves propagating along the auroral field lines.
Document ID
19850029393
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Gurnett, D. A.
(Iowa Univ. Iowa City, IA, United States)
Huff, R. L.
(Iowa, University Iowa City, IA, United States)
Menietti, J. D.
(Iowa Univ. Iowa City, IA, United States)
Burch, J. L.
(Iowa Univ. Iowa City, IA, United States)
Winningham, J. D.
(Southwest Research Institute San Antonio, TX, United States)
Shawhan, S. D.
(NASA Headquarters Washington, DC United States)
Date Acquired
August 12, 2013
Publication Date
October 1, 1984
Publication Information
Publication: Journal of Geophysical Research
Volume: 89
ISSN: 0148-0227
Subject Category
Geophysics
Report/Patent Number
AD-A150627
Accession Number
85A11544
Funding Number(s)
CONTRACT_GRANT: N00014-76-C-0016
CONTRACT_GRANT: F7121-83-N-0001
CONTRACT_GRANT: NGL-16-001-043
CONTRACT_GRANT: NAS5-26363
CONTRACT_GRANT: NGL-16-001-002
CONTRACT_GRANT: NAG5-310
CONTRACT_GRANT: NAS5-25693
Distribution Limits
Public
Copyright
Other

Available Downloads

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