Author: Hansli, M.
Paper Title Page
WEPF35 Current Status of the Schottky Cavity Sensor for the CR at FAIR 907
  • M. Hansli, R. Jakoby, A. Penirschke
    TU Darmstadt, Darmstadt, Germany
  • P. Hülsmann, W. Kaufmann
    GSI, Darmstadt, Germany
  Funding: This work was supported by the GSI. The author would like to thank the CST AG for providing CST Studio Suite.
In this paper the current status of the Schottky Cavity Sensor development for the Collector Ring at FAIR, a dedicated storage ring for secondary particles, rare isotopes, and antiprotons, is presented. Designed for longitudinal and transversal Schottky signals, the Sensor features a pillbox cavity with attached waveguide filters utilizing the Monopole mode at 200 MHz for longitudinal and the Dipole mode at around 330 MHz for transversal Schottky measurements. Separated coupling structures allow for mode-selective coupling to measure the different Schottky planes independently. A ceramic vacuum shielding inside the pillbox is implemented to enable non-hermetic adjustable coupling, tuning devices and waveguide structures. Simulations of the structure with focus on the impact of the coupling structures and the ceramic vacuum shielding on the R-over-Q values and the coupling are presented as well as measurements of a scaled demonstrator including comparisons with the simulations.
Cavity Design Questions  
  • M. Hansli
    TU Darmstadt, Darmstadt, Germany
  Matthias presented two cavity designs. His waveguide loaded 3 GHz monopole mode resonator is optimized as phase detector for low charge beams in a plasma wakefield experiment. We discussed his questions on the options of the waveguide-to-coaxial coupling, which often are very pragmatic, personal engineering solutions, sometimes just a matter of “taste”. His 2nd design was a dipole mode resonator, to be used as a Schottky pickup for FAIR (GSI). He shared some details on the optimization of the geometry, e.g. to maximize the R/Q. We agreed that he did a good job, and addressed most design issues very systematically.  
slides icon Slides FRWMJ3 [0.191 MB]