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  

Yamamoto, Y.

Paper Title Page
MOPP044 Cavity Diagnostic System for the Vertical Test of the STF Baseline 9-cell Cavity at KEK 643
 
  • Y. Yamamoto, H. Hayano, E. Kako, S. Noguchi, M. Satoh, T. Shishido, K. Umemori, K. Watanabe
    KEK, Ibaraki
  • S.-I. Moon
    POSTECH, Pohang, Kyungbuk
  • H. Sakai, K. Shinoe
    ISSP/SRL, Chiba
  • Q. J. Xu
    IHEP Beijing, Beijing
 
  Four 9-cell cavities, which are TESLA-type 9-cell cavities, were developed and tested in KEK for the future ILC project. A simple cavity diagnostic system was introduced to search the heating spot and to detect the x-ray emission. It is composed of the carbon resistors and the PIN photo diodes. They were attached on the equator of the cell, around the HOM couplers and on the end flanges. They were very effective to search the heating spot and to detect the x-ray emission during the vertical tests. All cavities eventually had the heating spot around the equator in the final state of the vertical test. It is conceivable that the quality of the electron beam welding was somewhat poor, when the dumbbells were connected. On this February, a new vertical test facility will be completed in STF (Superconducting RF Test Facility). Six 9-cell cavities will be tested by using the new system for S0 plan, which goal is the higher accelerating gradient for ILC. The new temperature and x-ray mapping system and new DAQ system will be introduced. This paper reports the recent status in the new vertical test facility in KEK-STF.  
MOPP131 Cryomodule Tests of the STF Baseline 9-cell Cavities at KEK 868
 
  • E. Kako, H. Hayano, S. Noguchi, N. Ohuchi, M. Sato, T. Shishido, K. Watanabe, Y. Yamamoto
    KEK, Ibaraki
 
  The STF-Baseline superconducting cavity system, which includes four TESLA-type 9-cell cavities, input couplers and frequency tuners, has been developed for the future ILC project. A 6m-cryomodule including one of four STF-Baseline cavities was assembled for the initial test called the STF Phase -0.5. The first cool-down of the cryomodule and high power tests of the STF-Baseline cavity had been successfully carried at 2 K. The maximum accelerating gradient (Eacc,max) of 19.3 MV/m was achieved in a specific pulse width of 1.5 msec and a repetition of 5 Hz, (23.4 MV/m in a shorter pulse of 0.6 msec). The onset of x-rays radiation was observed at higher field than 15 MV/m, and the measured Qo value was about 5 x 109 at 18 MV/m in accompanied with field emission. The detuning angle of about -13 degrees at 18 MV/m was successfully compensated to nearly zero by a combined operation with both an offset detuning and an optimised applied voltage in the piezo element. String assembly of four STF-Baseline cavities has been stated in Jan. 2008. The second cryomodule test for 4 cavities, called the STF Phase -1.0, is scheduled in this early summer.  
THXM02 Development of the KEK-B Superconducting Crab Cavity 2927
 
  • K. Hosoyama, K. Akai, K. Ebihara, T. Furuya, K. Hara, T. Honma, A. Kabe, Y. Kojima, S. Mitsunobu, Y. Morita, H. Nakai, K. Nakanishi, M. Ono, Y. Yamamoto
    KEK, Ibaraki
  • H. Hara, K. Okubo, K. Sennyu, T. Yanagisawa
    MHI, Kobe
 
  The development of the KEK-B superconducting crab cavity, including the design, production, tests and latest parameter performances should be described in this talk.  
slides icon Slides