START-TO-END JITTER SIMULATIONS OF THE LINAC COHERENT LIGHT SOURCE∗

The Linac Coherent Light Source (LCLS) is a fourth-generation light source demonstration project based on the self-amplified spontaneous emission (SASE) free-electron laser (FEL) concept. It will combine a new photoinjector, the Stanford Linear Accelerator Center (SLAC) linac, with two stages of bunch compression and a long undulator to create intense radiation pulses at 1.5 A. Successful opera-tion of the LCLS will require consistent delivery of a high-brightness electron beam to the undulator, in the face of effects such as wakefields and coherent synchrotron radia-tion (CSR). Because of the sensitivity to beam quality and subtle effects, it is necessary to perform integrated tracking from the cathode through the undulator. We report on the combined use of PARMELA, elegant, and GENESIS to perform these simulations, and in particular the simulation of pulse-to-pulse variation in FEL performance due to rf-and laser-related variation in the electron beam.