Plasma Wave Maps of the Magnetosphere

J. Green (1), S. Boardsen (2), S. Fung (1), L. Garcia (3), and B. W. Reinisch

(1) NASA Goddard Space Flight Center, Greenbelt, MD 
(2) L3 Communications, Largo, MD 
(3) Raytheon, ITSS, Landover, MD
(4) Center for Atmospheric Research, University of Mass. Lowell, Lowell, MA

The Earth's magnetosphere supports a rich variety of plasma waves. Two of
the most important aspects about plasma waves in space are their source
locations and emission mechanisms. Three decades of space plasma wave
research have shown that it is sometimes difficult to pinpoint plasma wave
source regions. Rarely do we know the exact site of wave generation, yet
this is the region where knowledge of a complete particle distribution is
needed to identify the free energy source and the wave generation mechanism.
Part of particle-wave comparison problems stem from the fact that there are
many types of plasma waves and these waves can propagate to large distances
from their source regions. We now have the opportunity to globally analyze
plasma waves in a quantitative and systematic fashion. Very high quality
plasma wave measurements from a variety of instruments are now in the NASA
National Space Science Data Center archive. When properly combined into a
3-D database, plasma wave measurements from missions such as Hawkeye,
Dynamics Explorer-1, Polar, and IMAGE, can be used to construct wave maps
that would statistically yield important source region information that may
be impossible to recognize previously. Plasma wave maps will allow us to
look for "hot spots" in the wave intensities, thereby identifying either the
source regions or sites of plasma wave amplification. In addition, plasma
wave maps can easily characterize an emissionŐs radiation pattern allowing
for the identification of a source location.  Examples of wave maps from
magnetospheric emissions such as plasmaspheric hiss, non-thermal continuum,
and auroral kilometric radiation will be discussed.

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Presentation at URSI National Radio Science meeting, 
Boulder, Colorado, USA, 4-8 January 2004