Measurement of the kicker coupling impedances in the SIS and ESR at GSI

At high particle intensities coherent transverse beam oscillations may be excited due to the coupling of the beam to individual accelerators components. The characteristic values to describe these beam instabilities are the longitudinal- and transverse coupling impedances. One reason for this beam instability is the inductive interaction between the beam and the lumped kicker magnets. The type of the magnet, e.g. window-frame magnet or C-magnet, and his external electric network are the most important quantities to identify the coupling impedances below the cut-off frequency (for waveguide modes) of the beam pipe. For the kicker modules in the SIS and ESR accelerators at GSI theoretical calculations and measurement are presented