Pulsed xenon lamp at low current

Pulsed xenon lamps differ mainly from flash tubes in the way they are driven. Instead of discharging a capacitor into single intense flashes, the arc in those lamps operates in the burst regime typically at twice the AC mains frequency (i.e., 100 pulses per second on 50-Hz mains), fed by a transformer-capacitor circuit. The present Philips model 126564 was made in the 1960s and is designed to dissipate 100 W for an operating voltage of 450-630 V. Here I run it at high voltage (several kV) and low current (25-30 mA), which results in a filamentary plasma which does fill the whole discharge tube. Interestingly there is a greenish glow that surrounds the plasma channel, which is caused by oxygen impurity in the xenon fill.