Research on Plasma Discharge for Plasma Processing of a 1.3 GHz Single-cell SRF Cavity

YANG Lei; WU Andong; LU Liang; LI Yongming; XU Xianbo; CHEN Long; LI Chenxing; SUN Liepeng; LI Chunlong; MA Wei; HE Tao; XING Chaochao; HE Yuan

doi:10.11804/NuclPhysRev.35.03.278

Field emission limits the accelerating gradient increase in SRF cavities. In order to reduce field emission of SRF cavities, the plasma processing experimental setup of a 1.3 GHz single-cell SRF cavity is designed and built to carry out plasma processing discharge research at room temperature. The electromagnetic field distribution is simulated and the external quality factor is optimized to provide a suitable discharge condition using CST software. It is explored that the physical property of Ar/Ar-O₂ discharge and the variation trend of electron excitation temperature with the changes of pressure, forward power and O₂ content in experiment. The result of residual gas analysis indicates that Ar/O₂ plasma processing can eliminate the carbide of the inner surface of cavity.

Research on Plasma Discharge for Plasma Processing of a 1.3 GHz Single-cell SRF Cavity

1. Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China;

2. University of Chinese Academy of Sciences, Beijing 100049, China

Funds: National Natural Science Foundation of China(91426303, 11475232, 11535016)

Received Date: 2018-06-05

Rev Recd Date: 2018-07-22

Publish Date: 2018-09-20

Key words:

Abstract: Field emission limits the accelerating gradient increase in SRF cavities. In order to reduce field emission of SRF cavities, the plasma processing experimental setup of a 1.3 GHz single-cell SRF cavity is designed and built to carry out plasma processing discharge research at room temperature. The electromagnetic field distribution is simulated and the external quality factor is optimized to provide a suitable discharge condition using CST software. It is explored that the physical property of Ar/Ar-O₂ discharge and the variation trend of electron excitation temperature with the changes of pressure, forward power and O₂ content in experiment. The result of residual gas analysis indicates that Ar/O₂ plasma processing can eliminate the carbide of the inner surface of cavity.

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Reference (15)

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Research on Plasma Discharge for Plasma Processing of a 1.3 GHz Single-cell SRF Cavity

doi: 10.11804/NuclPhysRev.35.03.278

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