Figure 1

(A) Discharge unit (a) and photo of the plasma jet (b): 1—quartz tube, 2—high voltage rod electrode, 3—grounded foil electrode, 4—spectral intensity recording strip area of 6 mm width with centerline at 2.0 cm from the electrode edge; (B) Voltage signal across the discharge gap: (a) duty cycle of \(\tau _{bunch} / T_{bunch} \approx 8\)%, (b) 50% and (c) 90%; (C) Current (a) and voltage (b) signal across the discharge gap during a voltage pulse period.