Thomson scattering from analytical plasmas

Electrons play an essential role in energy transfer and many other processes within analytical plasmas, so a complete characterization of any plasma requires spatially and temporally resolved data for the electron number density and temperature, as well as the electron energy distribution function. Thomson scattering provides a reliable non-intrusive means of determining inherently radially resolved absolute values for these fundamental parameters, without the assumptions about cylindrical symmetry or thermodynamic conditions in the plasma that are required by many other techniques. However, because of the relatively complex and expensive instrumentation required to perform successful Thomson scattering measurements, this method has not been widely applied in the field of analytical chemistry. The goal of this review was to clarify the history and theory of Thomson scattering, discuss the instrumental details that must be considered in a Thomson scattering experiment, and summarize the results of studies in which the technique has been applied to the characterization of analytical plasmas, in order to demonstrate the power of Thomson scattering as a tool for plasma characterization.