| Abstract: | A quantitative knowledge of the Ba/BaO dispensation rate is necessary in order to understand the physics and chemistry of dispenser cathode surfaces, and the consequent cathode activity. This paper discusses three devices for determining Ba/BaO evaporation rate: the quartz crystal microbalance, the quadrupole mass spectrometer, and the Becker diode. An improved Becker diode technique is described which eliminates the drawbacks of the classical methods, and therefore may be suitable for routine use. |
