1Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China 2State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, China 3University of Chinese Academy of Sciences, Beijing 100049, China
Abstract：The Nb$_{3}$Sn thin film cavity, having the potential to be operated at a higher temperature and higher gradient compared to the cavity made from bulk niobium, is one of the most promising key technologies for the next-generation radio-frequency superconducting accelerators. In our work, several 1.3 GHz single-cell TESLA-shaped Nb$_{3}$Sn thin film cavities, coated by the vapor diffusion method, were tested at Peking University and Institute of Modern Physics, Chinese Academy of Sciences. It was observed that the performance of the Nb$_{3}$Sn thin film cavities in the tests without the slow cooling down procedure and the effective magnetic field shielding was significantly improved by using a low temperature baking at 100 ℃ for 48 hours. Although the peak electric field of the cavity remained unchanged, the rapid drop of the unloaded $Q$ value ($Q_{0}$) with the increasing accelerating field ($Q$-slope) was effectively eliminated, resulting in an improvement of the $Q_{0}$ in the intermediate field region by $\sim $8 times. Furthermore, under better test conditions with the shielded magnetic field less than 5 mG and the slow cooling down procedure in the temperature range of 25–15 K, the $Q_{0}$ was still improved by about 20%. Our study shows that the low temperature baking can be an effective supplement to the effective post-treatment for the Nb$_{3}$Sn thin film cavity.
Radiation treatment of gaseous and liquid effluents for contaminant removal, Proceedings of a technical meeting, Sofia, 7–10 September 2004, IAEA, Vienna, 2005, IAEA-TECDOC-1473
Yang Z Q 2017 Study on Nitrogen Doping of High Purity Niobium Used for the Fabrication of Superconducting Radio Frequency Cavity, PhD Dissertation (Peking University) (in Chinese)
LU Xiang-Yang;QUAN Sheng-Wen;ZHANG Bao-Cheng;HAO Jian-Kui;ZHU Feng;LIN Lin;XU Wen-Can;WANG Er-Dong; WANG Fang;JIN Song;XIN Tian-Mu;YAO Zhong-Yuan; CHEN Jia-Er;ZHAO Kui. The First Nine-Cell TESLA Cavity Made in China[J]. 中国物理快报, 2008, 25(11): 3940-3941.
2021, Vol. 38 
