Fundamentals of Plasma Physics

6.2 Dielectric tensor 189

ce^2


^2

pe^2 

pi^2


^2

Figure 6.2: CMA diagram.

It is actually unnecessary to plot this very large set of wave normal surfaces because
it turns out that the qualitative shape (i.e., topology) of the wave normal surfaces changes
only at specific boundaries in parameter space and away from the these boundaries the
wave normal surface deforms, but does not change its topology. Thus, the parameter space
boundaries enclose regions of parameter space where the qualitative shape (topology) of
wave normal surfaces does not change. The CMA diagram, shown in Fig.6.2 charts these
parameter space boundaries and so provides a powerful method for classifying cold plasma