1. JPSP-CAS co-operation in Superconducting RF of BEPCII
Wang Guang-wei, Pan Wei-min, Sun YI ( 孙毅）
RF group of IHEP
Apr. 8, 2009

2. overall of SRF system of BEPCII

3. JSPS-CAS co-operation 500MHZ superconducting cavity
Main parameter of SRF of BEPC-II
Cavity voltage MV
Beam power / Ring kW
RF phase stability ±1º
RF voltage stability ±1％
RF Station phase º - 720º
250KW
RF amplifier
JSPS-CAS co-operation
500MHZ superconducting cavity
LLRF interlock
emergency
quench
arc P+ P_
Low level control

4. Key time of the co-operation in SRF of BEPCII (2004-2009)
2004~May, two superconducting cavities fabrication, processing, vertical test at KEK
Jun first high power horizontal test of SCC at china mainland in the history
Aug ×SCC installation into tunnel
2005~2008 LLRF & beam commissioning
2006~2009 IHEP coupler test at KEK

5. Cavity fabrication, processing, vertical test at KEK
Cavity assembly at KEK
HOM damper test

6. SC cavity was transported to tunnel after the final assembled

7. SCC Vertical test at KEK (Nov.2004~Feb.2005)
IHEP: G.Wang, W.Pan, Y.Sun, Z.Li, Q.Ma had taken part in SCC vertical test at KEK ( Nov.2004~Feb )

8. First high power horizontal test in IHEP (Jun.2006)
RF voltage >2MV Q0 > 5×108
radiation of E cavity is decreased after high power RF aging
Experts from IHEP,KEK,MELCO,SSRF taken part in the high power test

9. SCC high power test result:
(Jun.2006)
KEK: T.Furuya , K. Akai, S.Mitsunobu, MELCO: 荒川 雅德 SSRF: Liujf, Guq, Houht, IHEP: Wanggw, Panwm, Suny, Lizq, Maq, Xub, Lisp, Hek, Liuyp, Zhangc, Mal, Xuzx, wangjq, etc.
East SCC
West SCC
Static loss
30W
27W
Q0（2MV）
5.4×108
1.02×109
Q0（1.8MV）
9.8×108
1.28×109 Q0
1.7×109(1.5MV)
1.44×109(1.6MV) QL
2×105
1.92×105
RF Pulse aging 50Hz/duty 5%
Cut off RF power in a quench
SCC under RF pulse aging P-
P +
RF voltage
Reflect power
Input power
RF waveform to SCC

10. BEPCII cavities was installed at tunnel (Aug.2006)

11. Prof. K. Akai at LLRF design meeting ( IHEP Apr. 2004 )

12. LLRF commissioning at first beam run (2006~2007) Prof. K. Akai help
Input RF power
Reflect power
1.89 to 2.5GeV
SR-ring operation(24 hrs)
Vc 1.3MV
(East SCC)

13. High power test of IHEP coupler at KEK (in 2008)

14. IHEP coupler test results
The power reached
is 270kW. (April, 2008)
(highest power level in china)

15. (Got helps from Prof. T. Furuya and Prof. S. Mitsunobu)
Praperation works before the high power test of couplers fabricated by IHEP was doing at KEK
(Got helps from Prof. T. Furuya and Prof. S. Mitsunobu)
High pressure rinsing
( W.Pan, Q. Ma, T.Huang
T. Furuya ,S. Mitsunobu )

16. Future co-operation suggestion
Spare cavity of BEPCII ( it is now under the fabrication in china )
High power input coupler
Digital Low-level RF

17. Paper list:
W. Pan, Y. Sun, G. Wang, T. Furuya and S. Kurokawa, “Studies on Higher Order Modes　
in BEPC II Superconducting Cavity”, High Energy Physics and Nuclear Physics, Vol. 28, No. 3,
March, 2004, pp
(2) Z. Li and C. Zhang, “Study of Heavily Damped SC RF Cavity”, High Energy Physics
and Nuclear Physics, Vol. 27, No. 10, pp , 2003.
(3) T. Furuya, K. Akai, K. Hara, K. Hosoyama, A. Kabe, G. Katano, Y. Kojima, S. Mitsunobu, Y. Morita, H. Nakai and M. Yamaga, “Achievements of the Superconducting Damped Cavities in KEKB Accelerator”, Proc. of the 11th Workshop on RF-superconductivity, DESY, Germany, 8 – 12 Sept
(4) K. Akai, et al.,“RF Systems for the KEK B-Factory”, Nuclear Instruments and Methods in Physics Research, A 499, 2003, pp
(5) W.M. Pan, G.W. Wang, Y. Sun, Z.Q. Li, H.Y. Lin, B. Xu, Q. Ma, T.M. Huang, P. Sha, “High Power conditioning of the Input Coupler for BEPCII Superconductor Cavity”, Proc of the 13th Workshop on RF Superconductivity, Beijing, China, Oct
(6) Sun Yi , Wang Guangwei, Pan Weimin, Li Zhongquan, Ma Qiang, Lin Haiying, Li Shaopeng,
He Kun, Liu Yaping, Huang Hong, Xu Bo, wang Qunyao, Huang Tongming, “Commissioning of
BEPCII superconducting RF system”, Proc of the 13th Workshop on RF Superconductivity, Beijing, China, Oct
(7) Yaping Liu, Li Shaopeng, He Kun, Sang Minjing, Ge Rui, Lv Chongwei, Bian Lin, Zhang Zhuo, “Cryogenic System for BEPCII Superconducting Cavity”, Proc of the 13th Workshop on RF Superconductivity, Beijing, China, Oct
(8) Z.Q. Li, G.W. Wang, W.M. Pan, Y. Sun, S.P. Li, Q. Ma (IHEP). T. Furuya, S. Mitsunobu, K. Akai,
Y. Yamamoto, Y. Kijima, M. Arakawa, Y. Okada, “Fabrication and Test of the 500MHz SC Modules
for the BEPCII”, Proc of the 13th Workshop on RF Superconductivity, Beijing, China, Oct
(9) G.W. Wang , W.M. Pan, Y. Sun, Z.Q. Li, G.Y. Zhao, H.Y. Lin, Y.F. Xu, H. Huang, Q. Ma, B. Xu,
Q.Y. Wang, Y.P. Liu, P. Sha, T.M. Huang, R. Liu, R.H. Zeng, T. Furuya, S. Mitsunobu, K. Akai,
“BEPCII RF system”, Proc of the 13th Workshop on RF Superconductivity,
Beijing, China, Oct

18. Thanks to JSPS co-operation!
Summary
SRF system of BEPCII is one of the co-operation flowers between JSPS-CAS (KEK-IHEP) , just same as the blooming SAKURA at YU YUAN TAN park of BEIJING.
2004~2006, two SC cavities had been fabricated, processed, and tested in Japan; The first high power test had been successfully carried out in 2006 at IHEP. Two SRF systems above 1.5MV voltage have contributed to e+/e- collision beam over 2×500mA, and 2.5GeV/250mA of 100KW beam power in SR mode Since the end of 2006.
thank Prof. S.Kurokawa for his great contribution to the superconducting cavity co-operation between IHEP and KEK, thank to Professors: K.Akai, T.Furuya, S.Mitsunobu, K.Hosoyama, for their kind help.
Thanks to JSPS co-operation!