Parameters of the Plasma of a Large-Scale High-Voltage Discharge in Air at Reduced Pressures

Abstract

The Sprite device allows one to ignite an ~1-m-long pulsed high-voltage discharge detached from the metal chamber walls in both a uniform gas and a gas with a large-scale pressure gradient. A microwave interferometer, a magnetic probe, and optical photography are used to diagnose the discharge plasma. It is established that, at pressures of 0.05−1 Torr, the transverse profile of the diffuse discharge glow is close to the current profile. The plasma density in the diffuse discharge reaches 10¹² cm^–3. The results of interferometric measurements of the plasma density agree well with the values obtained from measurements of the current density in the approximation of a steady-state electron drift. The results obtained are necessary for laboratory modeling of high-altitude discharges in the Earth’s atmosphere.