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arXiv · 1306.0109

Physical design of FEL injector based on performance-enhanced EC-ITC RF gun

Tong-ning Hu·Qu-shan Chen·Yuan-ji Pei·Ji Li·Bin Qin
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Abstract

To meet requirements of high performance THz-FEL (Free Electron Laser), a compact scheme of FEL injector was proposed. Thermionic cathode was chosen to emit electrons instead of photo-cathode with complex structure and high cost. The effective bunch charge was improved to ~200pC by adopting enhanced EC-ITC (External Cathode Independently Tunable Cells) RF gun to extract micro-bunches, and back bombardment effects were almost eliminated as well. Constant gradient accelerator structures were designed to improve energy to ~14MeV, while focusing system was applied for emittance suppressing and bunch state maintenance. Physical design and beam dynamics of key components for FEL injector were analyzed. Furthermore, start-to-end simulations with multi-pulses were performed by using homemade MATLAB and Parmela. The results show that continual high brightness electron bunches with low energy spread and emittance could be obtained stably.

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Tong-ning Hu, Qu-shan Chen, Yuan-ji Pei, Ji Li, Bin Qin. 2013-06-01. Physical design of FEL injector based on performance-enhanced EC-ITC RF gun. https://doi.org/10.1088/1674-1137%2F38%2F1%2F018101

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