Author: Vogel, V.
Paper Title Page
FRWAJ3
How short should the cavity resonator be?  
 
  • V. Vogel
    DESY, Hamburg, Germany
 
  Vladimir discussed this question analytically, to better understand the resolution limit of a pill-box cavity BPM with respect to the bunch length and operation frequency. A good rule of thumb seems to be, try to make the length of the cavity resonator comparable to the bunch length. However, for accelerators with very short bunch length <<1mm, e.g. FEL drivers, this seems to be not applicable. In this case the presence of the signal component due to a beam angle cannot be avoided. Vladimir also presented the required suppression of unwanted modes to achieve 1nm resolution, which is in the order of 125¬Ö135dB.  
slides icon Slides FRWAJ3 [0.222 MB]