Atmospheric Pressure Argon Plasma Jets II － Diagnostics for Active Region in APJ by a Probe－

This paper describes the results of probe diagnostics in atmospheric pressure argon plasma jets (APJs) for the clarification of their internal structure. The probe is consisted with a fine stainless-steel wire and a resistor. Observed probe current waveforms contain both of displacement and conduction currents, thus they are separated into two components. As the probe position moved away from the nozzle, the remarkable variations in waveforms were found that the amplitude of the former decreased, whereas that of the latter increased. Hence, we called them as “active region” of APJs and investigated their behavior. From the results, we recognized the existence of the active region positioned at the downstream from the brilliant region in the APJs as the natural character without the probe insertion. © 2024 The Institute of Electrical Engineers of Japan.