Observations of electron gyroharmonic waves and the structure of the 10 torus
Journal Article
·
· J. Geophys. Res.; (United States)
Narrow-banded emission were observed by the planetary radio astronomy experiment on the Voyager 1 spacecraft as it traversed the Io plasma torus. These waves occur between harmonics of the electron gyrofrequency and are the Jovian analogue of electrostatic emissions observed and theoretically studied for the terrestrial magnetosphere. The observed frequencies always include the component near f/sub uhr'/ the upper hydbrid resonant frequency, but the distribution of the other observed emissions varies in a systematic way with position in the torus. A detailed discussion of the observations is presented. A refined model of the electron density variation, based on identification of the f/sub uhr/ line, is also included. Spectra of the observed waves are analyzed in terms of the linear instability of an electron distribution function consisting of isotropic cold electrons and hot loss cone electrons. The positioning of the observed auxiliary harmonics with respect to f/sub uhr/ is shown to be an indicator of the cold to hot temperature ratio T/sub C//T/sub H/. It is concluded that this ratio increases systematically by an overall factor of perhaps 4 or 5 between the inner (Lapprox.5 R/sub J/) and outer (Lapprox.9 R/sub J/) portions of the torus. Other relevant plasma and spectroscopic data are discussed.
- Research Organization:
- Laboratory for Extraterrestrial Physics, Goddard Space Flight Center, Greenbelt, Maryland 20771
- OSTI ID:
- 5671865
- Journal Information:
- J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 86:A10; ISSN JGREA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Detection of Jovian whistler mode chorus; implications for the Io torus aurora
Electrostatic waves in the Jovian magnetosphere
Standing hydromagnetic waves in the Io plasma torus: Voyager 1 observations
Journal Article
·
Mon Dec 31 23:00:00 EST 1979
· Geophys. Res. Lett.; (United States)
·
OSTI ID:5391650
Electrostatic waves in the Jovian magnetosphere
Journal Article
·
Mon Dec 31 23:00:00 EST 1979
· Geophys. Res. Lett.; (United States)
·
OSTI ID:5391609
Standing hydromagnetic waves in the Io plasma torus: Voyager 1 observations
Journal Article
·
Tue Oct 31 23:00:00 EST 1989
· Journal of Geophysical Research; (USA)
·
OSTI ID:5917802