Errata: "Theory of Electrostatic Double Probe Comprised of Two Parallel Plates"

The difficulties with continuum single probes in plasma diagnostics may arise from the uncertainties surrounding the other electrode (ground), which usually does not assume the plasma potential at the point of interest, and from the fact that the probe disturbs the plasma to a much greater extent than that predicted by classical theories. In order to circumvent these difficulties, the present paper analyzes the double probes comprised of two parallel plates. Because of the simple geometry, the complete flow region between the two electrodes, comprised of two boundary layers and an in viscid layer, can be analyzed in detail. The governing equations for the electrical and flow properties of the continuum, weakly ionized plasma are solved. The cases of electron temperature in frozen state, with respect to the neutral gas temperature, and in equilibrium are considered. From the solution, simple equations are derived which can be used to translate the potential-current characteristics of the probe into the electron temperature and number density of the freestream plasma. The analysis also shows the detailed mechanism by which electricity is conducted between two plates across a flowing plasma.