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arXiv · 2012.04817

Medium-temperature furnace bake of Superconducting Radio-Frequency cavities at IHEP

Feisi He·Weimin Pan·Peng Sha·Jiyuan Zhai·Zhenghui Mi·Xuwen Dai·Song Jin·Zhanjun Zhang·Chao Dong·Baiqi Liu·Hui Zhao·Rui Ge·Jianbing Zhao·Zhihui Mu·Lei Du·Liangrui Sun·Liang Zhang·Conglai Yang·Xiaobing Zheng
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Abstract

Recently, heat treatment between 250 C and 500 C has been attempted to improve quality factor of superconducting radio-frequency cavities at FNAL and KEK. Experiments of such medium temperature (mid-T) bake with furnaces have also been carried out at IHEP. Firstly, eleven 1.3 GHz 1-cell cavities were treated with different temperatures at a small furnace. The average quality factor has reached 3.6E10 when the gradient is 16 MV/m. Then, the recipe of mid-T furnace bake at 300 C for 3 hours has been applied to six 1.3 GHz 9-cell cavities at a new big furnace. The average quality factor has reached 3.8E10 when the gradient is 16 MV/m.

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Feisi He, Weimin Pan, Peng Sha, Jiyuan Zhai, Zhenghui Mi, Xuwen Dai, Song Jin, Zhanjun Zhang, Chao Dong, Baiqi Liu, Hui Zhao, Rui Ge, Jianbing Zhao, Zhihui Mu, Lei Du, Liangrui Sun, Liang Zhang, Conglai Yang, Xiaobing Zheng. 2020-12-09. Medium-temperature furnace bake of Superconducting Radio-Frequency cavities at IHEP. https://arxiv.org/abs/2012.04817

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