|
- K. Saito, S. Chouhan, C. Compton, J. DeKamp, M. Leitner, F. Marti, J.P. Ozelis, S. Shanab, G.J. Velianoff, X. Wu, Y. Yamazaki, A. Zeller, Y. Zhang, Q. Zhao
FRIB, East Lansing, Michigan, USA
- S.K. Chandrasekaran
MSU, East Lansing, USA
- K. Hosoyama
KEK, Ibaraki, Japan
|
|
|
To date SRF technology is extending to large scale heavy ion LINACs, where SRF cavities accelerate beams from very low energy to high energy. In this application, superconducting (SC) solenoids are installed inside the cryomodule to provide strong beam focusing with enhanced space efficiency. FRIB will use local magnetic shielding, where magnetic shielding by Cryoperm or A4K is located close to the cavity at 2K. In this scheme rather strong magnetic fringe fields from the SC solenoid expose the shielding material and will magnetize it. An efficient degaussing process is required as cure against such magnetization. Magnetic material characterization of magnetic shielding materials is very important to be able to plan effective degaussing procedures. The paper will also discuss the design of FRIB solenoids optimized for cost, reliability, and robust long-term operation. NbTi wire performance criteria are discussed in addition to solenoid operational margins.
|
|