Particles from Electrodes with a Small Radius of Curvature During Pulsed Discharges in Air

This work presents a continuation of the study on the scattering of particles in a nanosecond spark discharge between two needle electrodes. Additional data were obtained on the scattering of electrode particles during voltage pulses of positive polarity with a half-maximum duration of 10 ns and a rise time of 2.2 ns, at atmospheric air pressure. Images of a discharge with particles flying away from a high-voltage electrode, obtained using a four-channel ICCD camera, are also presented. The study confirms that the formation of thin luminous tracks during diffuse and spark discharges is associated with the emission of metal particles from the surface of the electrodes. It is hypothesized that this process, similar to discharges in a vacuum, may involve mechanical phenomena that arise under the influence of a high electric field near needle electrodes.