An interpretation of Jupiter's decametric radiation and the terrestrial kilometric radiation as direct amplified gyroemission

Abstract

view Abstract Citations (131) References (73) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS An interpretation of Jupiter's decametric radiation and the terrestrial kilometric radiation as direct amplified gyroemission. Melrose, D. B. Abstract Direct amplified gyroemission due to an anisotropic distribution of suprathermal electrons is proposed as the most plausible emission mechanism for Jupiter's decametric radiation (DAM) and the terrestrial auroral kilometric radiation (AKR). It is suggested that the required electron distribution could be produced by electrons, initially with small pitch angles, precipitating from the magnetosphere. A quasi-linear treatment of the proposed mechanism is outlined, including satisfaction of the Doppler condition, calculation of the growth rate, conditions for quasi-linear relaxation, and generation of the anisotropy. The mechanism is applied to the Jovian DAM, emphasizing the growth rate, the power radiated, and the elliptical polarization of the radiation. It is found that the theory can account for the gross features of the DAM, provided the number density in the precipitating electron streams exceeds 20 per cu cm. Application of the theory to the AKR shows that the requirements concerning the properties of the precipitating electrons appear to be satisfied by the observed properties of those inverted V events which correlate with the emission of AKR. Publication: The Astrophysical Journal Pub Date: July 1976 DOI: 10.1086/154532 Bibcode: 1976ApJ...207..651M Keywords: Auroral Irradiation; Decametric Waves; Jupiter (Planet); Planetary Magnetospheres; Planetary Radiation; Terrestrial Radiation; Brightness Temperature; Conservation Equations; Correlation; Electron Distribution; Elliptical Polarization; Fine Structure; Lines Of Force; Astrophysics full text sources ADS |