• E. Kako, S. Noguchi, M. Sato, T. Shishido, K. Watanabe, Y. Yamamoto
  KEK, Ibaraki
• H. Jenhani
  LAL, Orsay
• T.X. Zhao
  IHEP Beiing, Beijing

High power tests of the STF cryomodule including four MHI cavities and STF-1 input couplers were carried out at KEK. The maximum input rf power of 360 kW was successfully transfered to the cavity operated at high gradients at 2 K. After the cryomodule tests, the conditioning test of the coupler at room temperature was carried out, and rf processing up to 650 kW (1.5 ms and 5 Hz) was achieved. TTF-V couplers were shipped from LAL to KEK, and the high power test was carried out at KEK-STF. Rf processing up to 2 MW in the short pulse of 400 us (5 Hz) and 1 MW in the long pulse of 1.5 ms (5Hz) was demonstrated. The results of the coupler processing at KEK will be reproted in this talk.

Slides

Talk

• J.Y. Zhai, Y.L. Chi, J.P. Dai, J. Gao, J. Gu, M. Hou, Z.Q. Li, J. Yu, J.R. Zhang
  IHEP Beijing, Beijing
• J.Z. Chen, J.Q. Qiao
  HJL, Beijing
• J.X. Wang, H. Yu, H. Yuan
  BIAM, Beijing
• W.P. Xie
  OTIC, Ningxia
• T.X. Zhao
  TIPC, BeiJing

As the key component of the “IHEP 1.3 GHz SCRF Accelerating Unit and Horizontal Test Stand Project”, a low-loss shape bare tube 9-cell cavity using Ningxia large grain niobium is being fabricated at IHEP. This paper presents the fabrication procedure and frequency tuning method of the dumbbells of this cavity. Due to the special properties of the large grain material, several mechanical and RF problems were found and successfully solved. After equator welding, this cavity will be surface treated and tested late this year.

Poster