Coupling impedance of vacuum pumping holes for the APS storage ring

摘要

The coupling impedance of a single slot in a thick wall beam pipe was measured. The slot dimension is small compared to the wavelength of interest. The measurements were done by the wire method with the synthetic pulse technique. The gating technique was also applied to obtain the reflection response for a structure that does not have appropriate calibration standards. The measured results are in good agreement with calculated impedance using analytical formulae given by other authors.