Published online by Cambridge University Press: 24 October 2008
Some experiments are described in which the efficiency of ionisation of potassium at a hot molybdenum surface was investigated. The degree of ionisation observed is consistent with the most recent measurements of the electron work function of molybdenum.
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∥ loc. cit.
* Meyer herself interprets her results assuming for Φe a value of 4·66 volts obtained by measuring the electron emission from the filament in her apparatus, but in view of the uncertainties of her temperature scale it is not possible to place very much reliance on this value. If such a value was correct, the ionisation efficiency should exceed 98 %.
* loc. cit.
* With the low filament temperatures here employed, the temperature distribution over even the central portion of the filament is far from uniform. This departure from uniformity will have the effect of smoothing out any discontinuous transition, such as that which Killian observed, between the portions AB and BC of the curves.
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