Author: Yi, C.H.
Paper Title Page
MOPC035 Design and Machine Features of 2.2-m C-band Accelerating Structure 148
  • C.H. Yi, M.-H. Cho, S.H. Kim, H. Lee
    POSTECH, Pohang, Kyungbuk, Republic of Korea
  • W. Namkung
    PAL, Pohang, Kyungbuk, Republic of Korea
  Funding: This work is partly supported by the MEST, Korea and POSTECH BK21 Program. And this work was supported by the Korea Student Aid Foundation (KOSAF) grant funded by the Korea government.
A compact linac system is designed using a longer accelerating column in a C-band linac. It reduces the total number of RF units for the given linac beam energy and results in the cost-effective use of RF powers. For the 10 GeV PAL-XFEL project, a C-band accelerating column of 2.2-m long is investigated, which is 22% longer than 1.8-m for the SACLA at SPring-8. The detailed RF and thermal characteristics are presented by an analytic model.
TUPS014 Vacuum Performance Simulation of C-band Accelerating Structures 1548
  • H. Lee, M.-H. Cho, S.H. Kim, C.H. Yi
    POSTECH, Pohang, Kyungbuk, Republic of Korea
  • W. Namkung, C.D. Park
    PAL, Pohang, Kyungbuk, Republic of Korea
  Funding: This work is partly supported by the MEST and POSTECH Physics BK21 program.
A C-band accelerating structure has a higher accelerating gradient than that of the S-band structure. It provides a good advantage of a shorter machine length. In order to effectively use RF power and for cost reduction, the accelerating structure should be as long as possible. We propose a 2.2-m long structure compared to 1.8-m at SACLA (SPring-8 Angstrom Compact free electron LAser). However, a longer accelerating structure has worse vacuum performance than a shorter accelerating structure. Thus, the vacuum conductance of 2.2-m long structure has to be checked. We calculate vacuum performance of the accelerating structure by 1-D analytical method and 3-D finite element method (FEM). It is shown that the vacuum performance for the 2.2-m long accelerating structure is safe enough for the XFEL LINAC.