Author: Stovall, J.
Paper Title Page
THPWO050 High Power Test and Beam Commissioning of he CPHS RFQ Accelerator 3884
 
  • Q.Z. Xing, C. Cheng, L. Du, Q. Du, T. Du, C. Jiang, H.T. Lu, J. Ni, Q. Qiang, C.-X. Tang, X.W. Wang, Y.G. Yang, H.Y. Zhang, S.X. Zheng
    TUB, Beijing, People's Republic of China
  • J.H. Billen
    Self Employment, Private address, USA
  • W.Q. Guan, Y. He, J. Li
    NUCTECH, Beijing, People's Republic of China
  • X. Guan
    Tsinghua University, Beijing, People's Republic of China
  • J. Stovall
    STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
  • L.M. Young
    LMY Technology, USA
 
  Funding: Work supported by the “985 Project” of the Ministry of Education of China, National Natural Science Foundation of China (Major Research Plan Grant No. 91126003 and 11175096).
We present, in this paper, the high power test result and the beam commissioning status of a Radio Frequency Quadrupole (RFQ) accelerator for the Compact Pulsed Hadron Source (CPHS) at Tsinghua University. The 3-meter-long RFQ is designed to deliver 3 MeV protons to the downstream High Energy Beam Transport (HEBT) with the peak current of 50 mA, pulse length of 0.5 ms and beam duty factor of 2.5%. The RFQ has been designed, manufactured, and installed at Tsinghua University. High-vacuum test of the RFQ has been carried out carefully and the cooling system has been mounted. At the beginning of 2013, the high power RF test has been performed and the first 3 MeV proton beam is obtained.
 
 
THPWO075 Beam Loss Limits in High Power Proton Linear Accelerators 3930
 
  • L. Tchelidze
    ESS, Lund, Sweden
  • J. Stovall
    STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
 
  High power hadron linear accelerators are designed based on 1 W/m loss limit criteria. The loss limit originates from the hands-on-maintenance allowance of the accelerators and limits average dose rate level to less than 0.1 - 1 mSv/hr at 30 cm from a machine after 100 days of continuous operation and 4 hours of down time. However, machine activation and thus beam loss limit depends on incident particle energy and 1 W/m is only a good approximation for energies 100-200 MeV and higher (in H-/H+ accelerators). At lower energies though, one could allow much higher than 1 W/m without excess activation. A careful analysis of energy dependent loss limits was performed for proton linacs as part of the study for the European Spallation Source (ESS) linac, for energy ranges 5 MeV – 2.5 GeV. ESS linac is to be built in Lund, Sweden and will deliver 5 MW proton beam to the target. MARS code was used for calculations and beam loss limits were derived as a function of energy.  
 
WEPFI075 Design of the FRIB RFQ 2866
 
  • N.K. Bultman, G. Morgan, E. Pozdeyev, Y. Yamazaki, Q. Zhao
    FRIB, East Lansing, USA
  • J. Stovall, L.M. Young
    TechSource, Santa Fe, New Mexico, USA
 
  Funding: This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661
FRIB linac driver includes a front end and a SRF linac for all stable ion beams with energy more than 200 MeV/u, and beam power on target up to 400 kW. A 80.5 MHz FRQ at the front end accelerates heavy ion beams from 12 keV/u to 0.5 MeV/u, in CW mode. Design of the RFQ is introduced and several important technical issues are discussed in this paper.