Vacuum discharge driven by a magnetic pulse compression circuit

Low pressure discharges in a compact coaxial geometry were produced by applying either positive or negative high voltage pulses delivered by a three-stage magnetic pulse compression circuit. The driver provided repetitive pulses of up to 15 kV and 20 J maximum transferred energy per pulse. The inner electrode was a rod having either a pointed or flat end with sharp edges. When using the negative flat-end electrode, the breakdown occurred down to lower pressures (about 2.5 mPa), the discharge was confined inside the interelectrode gap and the discharge current had higher values (around 4 kA), the discharge characteristics being very reproducible. The measurements suggested that the field effect was responsible for the discharge onset in this configuration