Auroral Hiss Observed by Antarctic Rockets, S-210A-20 and 21 (e. Event Session) (Proceedings of the Second Symposium on Coordinated Observations of the Ionosphere and the Magnetosphere in the Polar Regions : Part II)

Abstract

Characteristics of auroral hiss emissions observed in the Antarctic rocket experiments using the S-210JA-20 and 21 rockets are described.The S-210JA-20 rocket was launched in a geomagnetically disturbed condition. whereas the S-210JA-21 was launched in a calm condition, although the both penetrated into auroras. From the ratio of the electric field intensity to the magnetic field intensity, the hiss emissions observed on the above two rockets are identified as the whistler mode. The Poynting fluxes of the auroral hiss observed on the rockets are compared with those observed on the ground and the difference in the flux is found to be ascribed to the attenuation through the lower ionosphere. Time variations of the VLF noise intensity observed on the rockets are compared with those of electron flux of 40-60 keV and electron density simultaneously observed on the same rockets. It is found that the VLF noise level corresponding to the auroral hiss is well correlated with the electron flux in the S-210JA-20 experiment, but the correlation is not good in the S-210JA-21 experiment.