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arXiv · 1402.6999

First Operation of an Ungated Diamond Field-Emission Array Cathode in a L-Band Radiofrequency Electron Source

P. Piot·C. A. Brau·B. K. Choi·B. Blomberg·W. E. Gabella·B. Ivanov·J. Jarvis·M. H. Mendenhall·D. Mihalcea·S. Panuganti·P. Prieto·J. Reid
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Abstract

We report on the first successful operation of a field-emitter-array cathode in a conventional L-band radio-frequency electron source. The cathode consisted of an array of $\sim 10^6$ diamond diamond tips on pyramids. Maximum current on the order of 15~mA were reached and the cathode did not show appreciable signs of fatigue after weeks of operation. The measured Fowler-Nordheim characteristics, transverse beam density, and current stability are discussed. Numerical simulations of the beam dynamics are also presented.

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P. Piot, C. A. Brau, B. K. Choi, B. Blomberg, W. E. Gabella, B. Ivanov, J. Jarvis, M. H. Mendenhall, D. Mihalcea, S. Panuganti, P. Prieto, J. Reid. 2014-02-27. First Operation of an Ungated Diamond Field-Emission Array Cathode in a L-Band Radiofrequency Electron Source. https://doi.org/10.1063/1.4884375

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