3-D Particle Modeling of Positive Streamer Inception From a Needle Electrode in Supercritical Nitrogen

Positive streamers need a source of free electrons ahead of them to propagate. Here we investigate a possible source of these electrons in high density media: field ionization. Zener´s model is used to obtain the field ionization rate of free electrons from impurities. Including this effect, we simulate the inception of positive streamers in supercritical N₂, in a needle-to-plane electrode geometry. Our 3-D particle simulation shows how the discharge branches into positive streamer channels around the electrode.