Periodic inhomogeneities in the glow of a diffuse plasma jet during a discharge in low-pressure air

Experimental data on the inhomogeneous glow of pulsed discharge plasma at air pressures of 0.4 and 1 Torr were obtained. The breakdown was carried out in quartz tubes with internal diameters of 1.8 and 8.4 cm, which were arranged in series. A transition from the regime of plasma diffuse jets (PDJs) with a uniform distribution of radiation intensity to a regime with the formation of a periodic structure has been discovered. It is shown that the second mode is caused by the appearance of additional peaks of microsecond duration on the main voltage and current pulses of the discharge.