Electron drift velocities in xenon and xenon‐nitrogen gas mixtures

The drift velocity of an electron swarm in pure xenon gas (99.995% pure) and xenon gas mixtures, containing 0.1%, 1%, and 10% nitrogen additive, was measured in a pulsed‐Townsend drift tube in order to observe the effects of the additives on electron mobility, and to demonstrate negative differential conductivity. The digitized signal was analyzed by a microcomputer to produce swarm drift time measurements. The amount of nitrogen necessary to perturb the electron drift velocity in pure xenon is implied from these measurements.