Author: Hajima, R.
Paper Title Page
THC04 Beam Simulations of High Brightness Photocathode DC Gun and Injector for High Repetition FEL Light Source 980
 
  • T. Miyajima, Y. Honda, X. Jin, T. Uchiyama, M. Yamamoto
    KEK, Ibaraki, Japan
  • R. Hajima, R. Nagai, N. Nishimori
    JAEA, Ibaraki-ken, Japan
  
  As a next gen­er­a­tion FEL light source based on linac, high rep­e­ti­tion rate op­er­a­tion to in­crease av­er­age FEL power has been pro­posed, e.g. LCLS-II pro­ject. The in­jec­tor, which gen­er­ates high bright­ness and high av­er­age cur­rent beam, is one of key com­po­nents. A pho­to­cath­ode DC gun and su­per­con­duct­ing RF cav­i­ties, which are de­vel­oped for ERL light source, can be em­ployed for the high rep­e­ti­tion rate in­jec­tor. For high rep­e­ti­tion rate op­er­a­tion of FEL light source, in­jec­tor sim­u­la­tions were car­ried out based on ERL in­jec­tor with demon­strated hard­ware per­for­mance by the cERL beam op­er­a­tion in KEK. The op­ti­miza­tion re­sults show that the gun volt­age of 500 kV is help­ful to achieve low emit­tance. In ad­di­tion, to es­ti­mate op­ti­mum gun volt­age and cav­ity ac­cel­er­a­tion gra­di­ent for the FEL op­er­a­tion, two op­ti­miza­tions with dif­fer­ent in­jec­tor lay­outs were car­ried out. The re­sults show that the both dif­fer­ent lay­outs have po­ten­tial to achieve tar­get emit­tance for FEL op­er­a­tion. Under the re­al­is­tic op­er­a­tion con­di­tion, the trans­verse nor­mal­ized rms emit­tance of 0.8 mm mrad with the rms bunch length of 3 ps, the bunch charge of 325 pC, and the beam en­ergy of 10 MeV is ob­tained from the op­ti­miza­tions.  
slides icon Slides THC04 [3.796 MB]