Observations of the Relation of the Macroscopic Shape of the Plasmapause to
the Microscopic Generation of Escaping Non-Thermal Continuum Radiation

S. A. Boardsen (1), J. L. Green (1), S. F. Fung (1), B. Sandel (2), P.
Decreau (3), H. Matsumoto (4), and K. Hashimoto(4).

(1) NASA Goddard Space Flight Center, USA 
(2) University of Arizona Lunar & Planetary Laboratory, USA 
(3) CNRS Laboratoire de Physique et Chimie de L'Environnment, France 
(4) Radio Atmospheric Science Center, Kyoto University, Japan


Case studies will be presented that relate observations of the plasmapause
(by the IMAGE spacecraft's Extreme Ultraviolet Imager and the Radio Plasma
Imager) with in-situ observations of escaping non-thermal continuum
radiation (by the IMAGE Radio Plasma Imager, the Geotail Plasma Wave
Instrument and the Cluster Whisper instrument).   Hashimoto et al. [JGR,
1997] showed that there is a high frequency extension of escaping continuum
termed kilometric continuum that would have to be generated deep inside the
nominal plasmapause location. Green et al.,  [JGR, 2001] presented one case
in which escaping continuum was associated with a plasmaspheric notch and
suggested that kilometric continuum was generated whenever the plasmapause
was pushed inwards from its nominal position. Green et al., [2001] also
suggested that the shape of the plasmapause strongly influences the
longitudinal beaming pattern of this radiation. Since then multiple events
have been identified in the IMAGE dataset. We will present observational
evidence that sheds light on questions like; what conditions are necessary
and or sufficient for the generation of escaping continuum? With IMAGE and
Cluster we will characterize the conditions in and near the source region.
With Cluster and Geotail we will characterize the spectrum of escaping
continuum outside of the source region and relate what is observed outside
with what is observed in or near the source region.

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35th Cospar Scientific Assembly, Paris France, July 18-25, 2004.