• F. Zhou, C. Adolphsen, Y.T. Ding, Z. Li, A.E. Vlieks
  SLAC, Menlo Park, California

SLAC is studying the feasibility of using an X-band RF photocathode gun to produce low emittance bunches for applications such as an MeV gamma source (in collaboration with LLNL) and an injector for a compact FEL. Systematic beam dynamics study are being done for a 5.5 cell X-band gun followed by several 53 cm long high-gradient X-band accelerator structures. A fully 3D program, ImpactT*, is used to track particles taking into account space charge forces, short-range longitudinal and transverse wakefields and the 3D rf fields in the structures, including the quadrupole component of the couplers. The effect of misalignments of the various elements (drive-laser, gun, solenoid and accelerator structures) are being evaluated. This paper presents these results and estimates of the expected bunch emittance versus bunch charge and cathode gradient.

*Ji Qiang, LBNL-62326, January 25, 2007.