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Abstract:
The Q-slope at high gradient affects the performance of superconducting cavity greatly. Recent researches show that low temperature (100—150)°C heat treatment (bake) has positive effects on the performance of superconducting cavities. A lot of cavity tests are analyzed based on bake treatment. The average gradient Eacc, max and Eacc at Q=1×1010 are increased by more than 3.5MV/m. Q at Eacc, max is increased and the Q-slope is improved. Analysis on bake temperature shows that higher bake temperature leads to higher Q value. Comparison of BCP and EP cavities shows that at least 60—80μm EP is needed for BCP surface. More than 10—15μm removal of the surface by BCP will degrade the performance of an EP cavity. Oxygen diffusion model is used to illustrate bake effect.
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References
[1]
|
. Visentin B et al. Cavity Baking: a Cure for the High Accelerator Field Q0 Drop. Proc. of the 9th Workshop on RF Superconductivity. Los Alamos National Laboratory, 1999.1982. Safa H. High Field Behavior of SCRF Cavities. Proc. of the 10th Workshop on RF Superconductivity. Tsukuba: KEK,2001. 2793. Lilje L et al. Electropolishing and In-Situ Baking of 1.3GHz Niobium Cavities. Proc. of the 9th Workshop on RF Superconductivity. Los Alamos National Laboratory, 1999. 744. Lilje L. High Accelerating Gradient in 1.3GHz Niobium Cavities. Proc. of the 10th Workshop on RF Superconductivity. Tsukuba: KEK, 2001. 2875. Kneisel P. Preliminary Experience with In-Situ Baking of Niobium Cavities. Proc. of the 9th Workshop on RF Superconductivity. Los Alamos National Laboratory, 1999. 3286. Visentin B. Change of RF Superconducting Parameters Induced by Heat Treatment on Niobium Cavities. Proc. of the 2001 Particle Accelerator Conference. Chicago: ANL,2001. 10567. Brinkmann R, Floettmann K, Rossbach J et al. TESLA Technical Design Report. Hamburg:DESY, 2001. Ⅱ-148. Palmer F L. IEEE Trans. Magn., 1987, 23(2): 16179. Grundner M, Halbritter J. J. Appl. Phys., 1979, 51: 39710. Bonin B. Materials for Superconducting Cavities. Proc. of CERN Accelerator School CERN96-03. Hamburg, 1996.19111. Hagen M. Internal Report, WU D 88-8. University of Wuppertal, March 198812. Knobloch J et al. High Field Q Slope in SC Cavities due to Magnetic Field Enhancement at Grain Boundaries. Proc. of the 9th Workshop on RF Superconductivity. Los Alamos National Laboratory, 1999. 7713. Halbritter J. Material Science of Nb RF Accelerator Cavities: Where doWe Stand 2001? Proc. of the 10thWorkshop on RF Superconductivity. Tsukuba: KEK, 2001. 29214. Halbritter J. IEEE Trans. on Appl. Supercond, 2001, 11:1864 |
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2007, 31(11): 1050-1055. |
[2] |
HUANG Wen-Xue
, WANG Yue
, ZHU Zhi-Chao
, TIAN Yu-Lin
, XU Hu-Shan
, SUN Zhi-Yu
, XIAO Guo-Qing
, ZHAN Wen-Long
. Experimental Study of the High-Voltage Breakdown and Simulations for the RFQ Cooler and Buncher RFQ1L. Chinese Physics C,
2006, 30(S2): 261-264. |
[3] |
LI Ming-Liang
, ZHU Sheng-Jiang
, CHE Xing-Lai
, YU Ying-Nan
. Research on Two-Quasiparticle Bands in 98Sr. Chinese Physics C,
2004, 28(S1): 75-77. |
[4] |
Yang Jianjun
, Ma Boqiang
, Li Guanglie
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1997, 21(2): 146-156. |
[5] |
BES Collaboration
. Experimental Study of Resonance f2(1270) in the J/ψ Hadronic Decay. Chinese Physics C,
1993, 17(2): 97-106. |
[6] |
Sa Ben-hao
, Zhang Xi-zhen
, Li Zhu-xia
, Shi Yi-jin
. A PRIMARY RESEARCH OF THE PHONON RENORMALIZATION OF NUCLEAR FIELD THEORY. Chinese Physics C,
1980, 4(3): 398-400. |
-
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