Author: Zhao, Q.
Paper Title Page
TUPPC011 Beam Steering Correction in FRIB Quarter-wave Resonators 1176
 
  • A. Facco
    INFN/LNL, Legnaro (PD), Italy
  • A. Facco, Y. Xu, Y. Zhang, Q. Zhao, Z. Zheng
    FRIB, East Lansing, Michigan, USA
 
  Funding: This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661
The Quarter-Wave Resonators (QWR) section of the FRIB superconducting driver linac is required to accelerate Uranium beam up to 16 MeV/u in two different charge states simultaneously. This puts severe requirements on resonators alignment and field quality, in order to avoid beam losses and emittance growth. In particular, QWR beam steering can cause transverse oscillations of the beam centroid which reduce the linac acceptance and induces emittance growth. We have studied, with an analytical model and with 3D beam dynamics simulations, correction methods for the FRIB QWRs steering. We found that cavity shifting can provide effective steering cancellation in FRIB QWRs without need of cavity shape modifications, and allows to eliminate transverse beam oscillations and to improve beam quality. Calculation and simulation methods and results will be presented and discussed.
Michigan State University designs and establishes FRIB as a DOE Office of Science National User Facility in support of the mission of the Office of Nuclear Physics.
 
 
MOPPR077 ION CHAMBERS AND HALO RINGS FOR LOSS DETECTION AT FRIB 969
 
  • Z. Liu
    IUCF, Bloomington, Indiana, USA
  • D. Georgobiani, M.J. Johnson, M. Leitner, R.M. Ronningen, T. Russo, M. Shuptar, R.C. Webber, J. Wei, X. Wu, Y. Yamazaki, Y. Zhang, Q. Zhao
    FRIB, East Lansing, USA
 
  Funding: This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661.
Unlike the high energy proton machines, our radiation transport simulation results show that it will be difficult to use traditional BLMs to detect beam losses for FRIB linac, not only due to the low radiation levels from low energy heavy ion beams, but also resulted by the cross talk effect from one part of the machine to another in the folded machine geometry. A device called “Halo Ring” is introduced as a component of the BLM system to substitute the traditional ion chamber in those regions.