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.