Bunch length measurements with the SPS AEW.31731 wall current monitor

The wall current monitor AEW.31731 is the workhorse for bunch profile measurements in the SPS. The way the pick-up is used, its transfer function and the transfer function of the whole bunch profile acquisition system is described. This information is used to deconvolve measured bunch profiles. A functional relation between the bunch length obtained from raw data and the bunch length obtained from deconvolved data is established. This relation can then be used to estimate the true bunch length without actually doing the deconvolution. Simulated bunch profile data confirm the functional relation found from experimental data.