Recombination of Atoms at the Surface of Thermocouple Probes

When atoms produced by a discharge at one end of a closed cylindrical tube diffuse down the tube, their rate of recombination on the walls of the tube can be determined by measuring the temperature of a probe traveling along the axis of the tube. However, the catalytic activity of the probe may, under specified conditions, appear to be the same whatever the catalytic activity of the probe material. This effect is offered as a possible explanation of the findings of Wood and Wise, who recently reported essentially the same recombination probability for hydrogen atoms on 12 different metals.