The measurement of Twiss parameters using segmented Faraday cups

The theory behind the use of segmented Faraday cups (SFCs) to measure beam emittance using a scanning slit is presented. A description of the electronics is given, and a sample of a beam profile and the results of an emittance measurement are presented. It is shown that the ability to combine the data using computers allows much more flexibility than only being able to center the beam in the pipe. Emittance measurements in two dimensions are straightforward and automatic. Beam center and width can be matched to expected values from beam optics codes, and magnets can be adjusted for corrections to very fine resolution