Measurements of streamer head potential and conductivity of streamer column in cold nonequilibrium atmospheric plasmas

This work presents a simple method for the characterization of streamers developing in cold atmospheric plasma jets. The method is based upon stopping (scattering) of streamers by means of an external dc potential in order to determine the potential of the streamer head. The experimental evidence presented in this work does not support the model of the electrically insulated streamer head. In fact, it shows that the electrode potential is transferred to the streamer head along the streamer column to which it is attached with no significant voltage drop. Based on the proposed method, we determine various streamer parameters such as head charge ((1-2)×10 ⁸ electrons), electrical field in the head vicinity (about 100kVcm ^-1), average conductivity (10 ^-2ω ^-1cm ^-1) and plasma density of the streamer column (2×10 ¹³cm ^-3).