Simulation of BPM and DC-monitor assembly for the NESTOR storage ring by   CST Studio Suite
  The piece of NESTOR vacuum chamber with the ceramic insertion for DC-monitor and RF-shields was simulated by using both transient and wake field solvers of CST Studio Suite. For a 6 mm gap between two RF-shields the contributions of the assembly considered to the longitudinal broadband (BB) impedance Z/n and the loss factor kloss are 0.71 Ohm and 0.21 V/pC, correspondingly. These estimates are the second largest after those of the RF-cavity that were obtained till now for the NESTOR ring components.   Contributions from a beam position monitor (BPM) are also obtained by simulation and compared with analytical estimates obtained earlier.   We also present in the paper the frequency content of longitudinal impedance in the frequency range from 0 to 16 GHz for all ring components considered. 
V. P. Androsov, A. M. Gvozd and Yu. N. Telegin
physics.acc-ph