Application of a pulsed probe for the diagnostics of a dense quiescent plasma in the presence of chemical reactions

The operation of an electric probe for cases of constant potential and its pulse variations is examined in the framework of continuum electrodynamics. Analytical approximate relationships between the total current recorded by the probe and the main parameters of the plasma are obtained. Results are given for a dense quiescent plasma with chemical ionization and recombination reactions. The theoretical relationships are confirmed experimentally for an air plasma generated behind the front of a reflected shock wave. Measurements of electron density performed with the electric probe are compared with measurements made with a microwave interferometer.