An Investigation into Some Properties of Proportional Counters

Abstract

Counters operating under conditions similar to those existing in cloud chambers (i.e. the counter gas was argon saturated with alcohol vapour, the total pressure being atmospheric) were studied, with the final aim of ascertaining the properties of a plate-wire-plate counter operating under the above conditions. Leakage problems due to the condensation of alcohol on the insulating surfaces were overcome. It was found that impurities were evolved from the alcohol on leaving it exposed to the argon atmosphere of the counter. The effect of these impurities on the output pulse height and on the pulse size distributions was studied. The output pulse height when particles were injected at varying distances from the centre wire, under different conditions of purity was found. A formula for the gas amplification factor of proportional counters is derived.