Keele Research Repository

Measurements of the electron drift velocity at room temperature in pure molecular hydrogen have been made for the E/p range between 40 and 360 volts.cm-1 .torr-1. Experimental conditions were arranged to minimalise the effects of space charge distortion of the applied electric field, of secondary processes, and of the time for initial equilibrium of the avalanche to be established.
The progress of single avalanches was monitored by photo­multipliers and un electron-multiplier in a pulsed time-of-flight method. The scattering of resonance radiation in the gas caused erroneous results to be recorded by the photomultiplier technique, but the electron-multiplier measurements yielded reliable data.