Author: Nasu, Y.
Paper Title Page
WEPFI024 Anisotropic Ferrite Magnet Focusing System for Klystrons 2756
  • Y. Fuwa, H. Ikeda, Y. Iwashita, R. Kitahara, Y. Nasu, H. Tongu
    Kyoto ICR, Uji, Kyoto, Japan
  • S. Fukuda, T. Matsumoto, S. Michizono
    KEK, Ibaraki, Japan
  The permanent magnet beam focusing for klystrons can eliminate the solenoid coil with the water cooling system and the power supply that consumes electricity. Hence the failure rate and the operating cost of RF systems should decrease. This feature is suitable for a large facility that requires a lot of klystrons such as ILC. Since the required magnetic field for klystron beam is moderate, inexpensive anisotropic ferrite magnets can be applied. The test model is fabricated for a 1.3 GHz klystron whose output power is 800 kW. Each magnet block in the model is movable for magnetic field adjustment and the iron yoke in the oil tank improves magnetic field distribution around cathode area. The result of a klystron power test will be presented.  
THPFI017 Development of Harmonic Field Measurement System with Higher Resolution ADC 3330
  • R. Kitahara, Y. Fuwa, Y. Iwashita, Y. Nasu
    Kyoto ICR, Uji, Kyoto, Japan
  Quadrupole magnets for ILC final focus should be enough strong with the limitation on the external radius, while the vibration of the magnetic center has to be highly avoided to keep the nm sized beam focusing stable at the interaction point a few m downstream from the lens. Gluckstern's 5-ring PMQ singlet seems a good candidate for the purpose, which is under investigation. The precise magnetic harmonic field measurement system is also under development for adjusting each magnet ring and evaluation of the assembled singlet. A rotating magnet system and a rotating coil system are prepared for the former and the latter purposes, respectively. Both systems have 24-bit ADC's for higher resolution. For the rotation coil, a flexible print circuit sheet, where a pair of one turn coils is printed on, is glued on a quartz rod. The two coils located on the quarts rod with the angle difference of 180 degree can separate the odd and even harmonics components by recording both the signals simultaneously to get their sum and difference. The two digitized signals are integrated digitally.