Measurements of Electron Drift Characteristics in Single Wire Gas Counter in Self-Quenching Streamer Transition Region

Measurements of the electron drift characteristics in a single wire gas counter operated in the transition region between proportional and self-quenching streamer (SQS) modes have been carried-out. The Ar-based gas mixtures with a small amount of ethanol vapor were used as the counting gas. As the results, the different behaviors of time response in both modes have been observed. The SQS mode operation gives superior properties on the time resolution, avalanche size (S/N ratio) and avalanche stability than those in proportional mode. The deduced basic data for the drift velocity in a single wire gas counter operated in SQS mode have a better consistency with the results measured by other groups using uniform field drift counter or other methods.