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arXiv · 2009.03933

Tungsten Thermionic Emission as a Gauge for Low Pressures of Cesium Vapor

João F. Shida·Fangjian Wu·Eric Spieglan·Mesut Çalışkan
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Abstract

Heated metal filaments under electric fields and low pressures of alkali metal gaseject electrons by thermionic emission as a function of the pressure of the gas and thetemperature of the filament. To explore this process in a program to develop large-area alkali metal photocathodes, we have designed and built a gauge following thestudies of Taylor and Langmuir. We present proof-of-principle measurements ofthe thermionic emission of a tungsten filament in cesium vapor. We describe a secondgeneration design that corrects flaws in the first gauge.

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João F. Shida, Fangjian Wu, Eric Spieglan, Mesut Çalışkan. 2020-09-08. Tungsten Thermionic Emission as a Gauge for Low Pressures of Cesium Vapor. https://doi.org/10.3390/instruments4040034

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