NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Observations of a free-energy source for intense electrostatic wavesSignificant progress has been made in understanding intense electrostatic waves near the upper hybrid resonance frequency in terms of the theory of multiharmonic cyclotron emission using a classical loss-cone distribution function as a model. Recent observations by Hawkeye 1 and GEOS 1 have verified the existence of loss-cone distributions in association with the intense electrostatic wave events, however, other observations by Hawkeye and ISEE have indicated that loss cones are not always observable during the wave events, and in fact other forms of free energy may also be responsible for the instability. Now, for the first time, a positively sloped feature in the perpendicular distribution function has been uniquely identified with intense electrostatic wave activity. Correspondingly, we suggest that the theory is flexible under substantial modifications of the model distribution function.
Document ID
19800052957
Document Type
Reprint (Version printed in journal)
Authors
Kurth, W. S.
(Iowa Univ. Iowa City, IA, United States)
Frank, L. A.
(Iowa Univ. Iowa City, IA, United States)
Gurnett, D. A.
(Iowa Univ. Iowa City, IA, United States)
Burek, B. G.
(Iowa, University Iowa City, Iowa, United States)
Ashour-Abdalla, M.
(Iowa, University Iowa City, Iowa; California University, Los Angeles, Calif., United States)
Date Acquired
August 10, 2013
Publication Date
May 1, 1980
Publication Information
Publication: Geophysical Research Letters
Volume: 7
Subject Category
Geophysics
Funding Number(s)
CONTRACT_GRANT: NAS5-20094
CONTRACT_GRANT: NAS5-20093
CONTRACT_GRANT: NGL-16-001-043
CONTRACT_GRANT: NSF ATM-76-13792
CONTRACT_GRANT: NGL 05-007-190
Distribution Limits
Public
Copyright
Other
No Preview Available