Role of catalyst to improve P-10 filled gas counter performance

The long-term performance of a ΔE gas counter filled with P-10 gas at a pressure of 130 Torr, and operated in the proportional mode, is monitored. The presence of iron-oxide based catalysts within the counter volume successfully removes electronegative impurities from outgassing and initial contaminants. It has been possible to operate this counter continuously for more than three months, with good resolution (9–10%). The initial slow decrease of peak channel with time has been attributed to the dynamic increase of electronegative impurities. It has been concluded that the long-term performance of a gas counter depends substantially on the concentration of the catalysts.