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arXiv · 2203.11598

Demonstration of sub-GV/m Accelerating Field in a Photoemission Electron Gun Powered by Nanosecond $X$-Band Radiofrequency Pulses

W. H. Tan·S. Antipov·D. S. Doran·G. Ha·C. Jing·E. Knight·S. Kuzikov·W. Liu·X. Lu·P. Piot·J. G. Power·J. Shao·C. Whiteford·E. E. Wisniewski
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Abstract

Radiofrequency (RF) electron guns operating at high accelerating gradients offer a pathway to producing bright electron bunches. Such beams are expected to revolutionize many areas of science: they could form the backbone of next-generation compact x-ray free-electron lasers or provide coherent ultrafast quantum electron probes. We report on the experimental demonstration of an RF photoemission electron source supporting an accelerating field close to 400~MV/m at the photocathode surface. The gun was operated in an RF transient mode driven by short $\sim 9$~ns X-band (\SI{11.7}{\giga\hertz}) RF pulses. We did not observe any major RF breakdown or significant dark current over a three-week experimental run at high accelerating fields. The demonstrated paradigm provides a viable path to forming relativistic electron beams with unprecedented brightness.

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W. H. Tan, S. Antipov, D. S. Doran, G. Ha, C. Jing, E. Knight, S. Kuzikov, W. Liu, X. Lu, P. Piot, J. G. Power, J. Shao, C. Whiteford, E. E. Wisniewski. 2022-03-22. Demonstration of sub-GV/m Accelerating Field in a Photoemission Electron Gun Powered by Nanosecond $X$-Band Radiofrequency Pulses. https://doi.org/10.1103/physrevaccelbeams.25.083402

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