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arXiv · 2408.14386

Experiment Research on Feasibility of In-Situ Plasma Cleaning in Normal-conducting Copper Cavities

Qianxu Xia·Lianmin Zheng·Yingchao Du
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Abstract

To assess the feasibility of in-situ plasma cleaning for copper cavities, a 13.56 MHz inductively coupled plasma platform with a built-in coil was developed at Tsinghua University. Experiments were conducted using this platform to optimize plasma discharge parameters and procedures specific to copper cavities. The results indicate that the "Ar/O + Ar/H method" significantly enhances the work function of the copper surface while reducing field enhancement effects induced by surface burrs. Consequently, this study confirms that in-situ plasma cleaning effectively mitigates field emission within copper cavities, thereby enhancing the stability and acceleration gradient of the accelerator system.

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Qianxu Xia, Lianmin Zheng, Yingchao Du. 2024-08-26. Experiment Research on Feasibility of In-Situ Plasma Cleaning in Normal-conducting Copper Cavities. https://arxiv.org/abs/2408.14386

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