Enhanced Escaping Terrestrial Continuum Radiation and Kilometric 
Continuum Radiation Observations and Implications

Anderson, R R,  Matsumoto, H,  Hashimoto, K,  Kojima, H,  Nagano, I,  
Yagitani, S,  Takano, H,  Carpenter, D L,  Kaiser, M L,  Bougeret, J

Enhanced escaping terrestrial continuum radiation has been shown to
be due to injected electrons from the plasmasheet drifting around
the earth eastward and impinging on portions of the plasmasphere
and magnetosphere where steep density gradients occur.
Electrostatic emissions at the local electron plasma frequency are
mode converted to electromagnetic radiation that propagates out
unless or until it encounters a region more dense than where it was
generated. Kilometric continuum radiation in the 100 kHz to 800 kHz 
frequency range first found in the GEOTAIL Plasma Wave Instrument 
(PWI) data has been believed to be due from a similar source 
mechanism but from much deeper within the plasmasphere. Both types 
of emissions contain much narrowband filamentary and fine structure. 
Narrowband filaments lasting many hours have been observed. The WIND 
Radio Science Experiment (WAVES) when near the Earth also frequently 
detects these emissions. By comparing the appearance of these 
emissions from two or more spacecraft we are able to deduce remotely 
the structure of the plasmasphere and magnetosphere. Some of the 
structure observed can be explained by the bulges, ducts, and 
irregularities known to exist in the plasmasphere. Comparisons of 
wave data from GEOTAIL and wave and imaging data from IMAGE 
indicated that some kilometric continuum events have their source in 
density bite-outs deep within the plasmasphere. Some of these 
bite-outs appear to last for several days as had previously been 
deduced from ISEE and CRRES number density measurements.