A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z  

Ma Q.

PaperTitlePage
TUP09High Power Conditioning of the Input Coupler for BEPCII Superconductor Cavity122
 
  • W. M. Pan, G. W. Wang, Y. Sun, Z. Q. Li, H. Y. Lin, B. Xu, Q. Ma, T. M. Huang, P. Sha
    IHEP, CAS
 
 High power conditioning and RF processing of the input coupler for BEPCII superconductor cavity (SCC) has been performed. Gas desorption is very important for a new input coupler; and high power conditioning and electron bombardment is quite effective for outgasing. For this reason, the DC bias voltage is applied to the conductors of coupler in the room temperature conditioning. RF power with full reflection of 150kW has been arrived under +(-)2000V DC bias voltage during the room temperature conditioning. At the same time, other methods have also been studied to improve the performance of input coupler during the beam operation. Up to now, the input coupler works well under the beam current of 250mA and beam energy is 2.5Gev, which means the input coupler can feed 100kW RF power to beam in continuous wave in normal operation. The details about the high power conditioning and RF processing of the input coupler will be given in the paper. 
WEP16Commissioning of BEPCII superconducting RF system477
 
  • Y. Sun, G. W. Wang, W. M. Pan, Z. Q. Li, Q. Ma, H. Y. Lin, S. P. Li, K. He, Y. P. Liu, H. Huang, B. Xu, Q. Y. Wang, T. M. Huang
    IHEP, CAS
 
 BEPC single-ring machine had been upgraded to BEPCII double-ring machine in the past four years, four 199.6MHz RT cavities were replaced by two 499.8MHz superconducting cavities. Two SRF stations of BEPCII had passed the first beam commissioning, physical problems such as changing frequency from 200MHz to 500MHz and compressing the bunch length in colliding mode, have been solved step by step. The engineering problems such as feeding 100KW beam power had also been solved. The SRF system of BEPCII project had finished on schedule. This paper gives a brief introduction to the commissioning of the SRF system of BEPCII. 
WEP23Fabrication and test of the 500 MHz SC modules for the BEPCII503
 
  • Z. Q. Li, G. W. Wang, W. M. Pan, Y. Sun, S. P. Li, Q. Ma
    IHEP, CAS
  • T. Furuya, S. Mitsunobu, K. Akai, Y. Yamamoto
    KEK
  • Y. Kijima, M. Arakawa, Y. Okada
    MELCO, Mitsubishi Electric Co. 
 
 Two KEKB type HOM damped SC cavities were constructed during past three years. These SC modules were re-designed to meet the RF frequency of 500 MHz of the BEPCII, the upgrade project of the Beijing Electron and Positron Collider, and have already been operated smoothly. It is a product of the successful collaboration among Mitsubishi Electric Co. (MELCO), KEK and IHEP of China. The cavity modules were fabricated and surface-treated by MELCO with the help and support of KEK. The vertical test of niobium cell, and the high power test of couplers and dampers were carried out in KEK, and the final acceptance tests were done in IHEP. 
WEP44The construction of the RF system of BEPC II584
 
  • 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
    IHEP, CAS
  • T. Furuya, S. Mitsunobu, K. Akai
    KEK
 
 In this article, we'll introduce the RF system of BEPCII to readers. It consists of 4 subsystems: superconducting cavity, high power klystron, cryogenic system and LLRF. The construction of the RF system had been finished in late 2006. During the last year of running till now, it has performed very well. 
WEP51Some fabrication issues on the spare high power input coupler for BEPCII superconductor cavities609
 
  • T. M. Huang, Q. Ma, W. M. Pan, G. W. Wang
    IHEP, CAS
 
 The BEPCII storage ring adopted two 500MHz superconducting cavities (SCC). The input coupler for the SCC is required to feed high RF power up to 150kW under continuous wave mode (CW). Considering the high power feeding and the compact structure of the coupler, the input coupler fabrication is challenged. Up to now, two units including windows and inner conductor (antennas) have been made by IHEP for the spare parts of BEPCII SCC input couplers. Some fabrication issues will be presented in this paper.