PRESERVING BRIGHT ELECTRON BEAMS: DISTORTED CSR KICKS

Short pulse, low emittance electron beams are necessary to drive bright FEL X-rays, for this reason it is important to preserve and limit emittance growth. The strong bunch compression required to achieve the short bunches, can lead to coherent synchrotron radiation (CSR)-induced emittance growth, and while there are some methods of CSR cancellation, these methods may be less effective when the CSR kicks are distorted. In an attempt to understand why CSR kicks become distorted, we compare the CSR kicks calculated using the whole beam parameters to the CSR kicks calculated using the longitudinally sliced beam parameters, when propagated to the end of the bunch compressor. We find that CSR kicks can become distorted when calculated with non-uniform slice beam parameters. While slice beam parameters that are uniform along the centre of the bunch, do not result in distorted CSR kicks.