Author: Wang, L.
Paper Title Page
TUPME017 Validation of the Microwave Instability in the Damping Ring of SuperKEKB using VFP Solver 1604
 
  • L. Wang
    SLAC, Menlo Park, California, USA
  • H. Ikeda, K. Ohmi, K. Oide, D. Zhou
    KEK, Ibaraki, Japan
 
  Microwave instability driven by CSR impedance in the damping ring of Super-KEKB is a concern due to its high bunch current. To understand the beam dynamics, we simulate the microwave instability using Vlasov-Fokker-Planck (VFP) solver. The longitudinal wake potential is calculated as a sum of the contributions due to vacuum chamber components distributed around the ring, including geometry wake field and CSR wake. To improve the accuracy of the simulation of microwave instability, the coherent synchrotron radiation impedance is calculated to very high frequency to get more accurate wake field with a short bunch. The CSR wake is much larger than the geometry wake. The threshold is just above the design current and saw-tooth type of instability is found above the threshold.