Author: Schaer, M.
Paper Title Page
MOPFI062 Optimization Studies for the SwissFEL RF-Gun 425
  • M. Schaer, A. Adelmann, A. Anghel, S. Bettoni, P. Craievich, L. Stingelin, C. Vicario, R. Zennaro
    PSI, Villigen PSI, Switzerland
  • Z. Zhang
    TUB, Beijing, People's Republic of China
  The 250 MeV SwissFEL injector test facility is in operation since August 2010. Measurements with the "CTF2 Gun 5" photocathode S-band rf-gun show promising beam parameters and satisfy the requirements of the SwissFEL project. Since the performance of the electron source is fundamental for the stability and brightness of a free electron laser, further gun optimization studies are pursued. Under investigation is currently a 3.6 cell C-band gun. First ASTRA simulations indicate that with this gun the peak-current can be increased, thanks to a shorter laser pulse and a higher initial acceleration, by almost a factor of two, at slightly better emittance values than the S-band "PSI Gun 1". Since the beam-quality depends also on the achieved performance of the cathode, several copper cathodes had been tested in the SwissFEL injector test facility to analyze the observed rapid degradation of quantum efficiency.