Remote Diagnostics of the Ambient Cold Plasma Density in the Low Altitude Trough 
Region Using the Radio Plasma Imager on the IMAGE Spacecraft

T. F. Bell, D. L. Carpenter, V. S. Sonwalkar, B. W. Reinisch, and M. Salvati

When the IMAGE spacecraft is in the low altitude trough region just outside the 
plasmasphere, the Radio Plasma Imager excites plasma waves in both the ordinary 
and extraordinary modes at LF and MF frequencies. A subset of these waves propagate 
towards the Earth, are reflected at lower altitudes, and return to IMAGE, where 
their time delay and dispersion are measured. In the present work we show how the 
properties of the reflected plasma waves can be used to determine the distribution 
of the cold plasma below the spacecraft.

_______________
Presented at the Fall American Geophysical Union Meeting, 
San Francisco, CA., December 15-19, 2000