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arXiv · 2501.02780

Design, fabrication and test of parallel-coupled slow-wave high-gradient structure for ultrashort input power pulses

Weihang Gu·Hao Zha·Jiaru Shi·Yuliang Jiang·Jiayang Liu·Xiancai Lin·Focheng Liu·Huaibi Chen
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Abstract

Tsinghua University has designed an X-band (11.424 GHz) slow-wave parallel-coupling accelerating structure, and demonstrated the high performance of the over-coupled structure operating with ultrashort pulse. In this study, we redesigned a 40-ns structure with 10 cells, tailored to the specifications of a high-power experimental platform, and provided a detailed analysis of the experimental results. Unexpected bead-pull results were observed during the cold testing, which we attribute to inter-cavity coupling. To explain these results, a multi-cell coupling circuit model was proposed and analyzed. High-power testing was conducted on the TPOT-X platform, and the highest gradient achieved was 130 MV/m after $1.1*10^7$ conditioning pulses. Compared to conventional multi-cavity high-gradient structures, the distributed power feeding system offers a shorter conditioning period and demonstrates the potential to achieve higher accelerating gradients under short-pulse operation.

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Weihang Gu, Hao Zha, Jiaru Shi, Yuliang Jiang, Jiayang Liu, Xiancai Lin, Focheng Liu, Huaibi Chen. 2025-01-06. Design, fabrication and test of parallel-coupled slow-wave high-gradient structure for ultrashort input power pulses. https://arxiv.org/abs/2501.02780

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