Author: Jia, Q.K.
Paper Title Page
MOPB15 Numerical Simulation of CAEP Compact FEL THz Source 35
 
  • L.J. Chen, Q.K. Jia
    USTC/NSRL, Hefei, Anhui, People's Republic of China
  • M. Li, X. Yang
    CAEP/IAE, Mianyang, Sichuan, People's Republic of China
  
  Free Elec­tion Laser Ter­a­hertz source is a good choice for THz source, whose wave­length is tun­able. Using 1D FEL stim­u­la­tion code FELO, we sim­u­late the out­put char­ac­ter­is­tic of China Acad­emy of En­gi­neer­ing Physics (CAEP) FEL THz, which is a wave­guide FEL os­cil­la­tor. The beam qual­i­tys’ in­flu­ence on the op­er­a­tion of FEL, such as en­ergy dis­per­sion, emit­tance and beam cur­rent, have been stud­ied to des­ig­nate a set of beam pa­ra­me­ters. Be­sides, the out­put per­for­mance of FEL at dif­fer­ent out­put cou­pling ratio is an­a­lyzed. The cav­ity de­tun­ing is dis­cussed too. Mean­while the in­flu­ence of the po­si­tion of the un­du­la­tor in the cav­ity on the FEL per­for­mance is also stud­ied.  
 
MOPC10 Numerical Investigation of Longitudinal Coherence in a Linear Tapered SASE FEL 118
 
  • H.T. Li, Q.K. Jia
    USTC/NSRL, Hefei, Anhui, People's Republic of China
  
  One goal of the sev­eral FEL fa­cil­i­ties op­er­at­ing in soft X-ray range, is the pro­duc­tion of high-gain nar­row-band­width FEL. In this re­port, the per­for­mance of ra­di­a­tion power and lon­gi­tu­di­nal co­hence is stud­ied for x-ray FEL gen­er­ated through sev­eral dif­fer­ent meth­ods, in­clud­ing ta­pered，in­verse-ta­pered and step-ta­pered un­du­la­tor, and the SASE-FEL ap­ply­ing dis­trib­uted op­ti­cal kly­stron. Three–di­men­sional sim­u­la­tion demon­strate that these meth­ods all can in­crease the FEL power and im­prove the time and spec­trum struc­ture with their own pa­ra­me­ter op­ti­miza­tion. In par­tic­u­lar, FEL gen­er­ated from toothed un­du­laor is stud­ied. It is shown that the lon­gi­tu­di­nal co­hence is im­proved and a se­ries of sev­eral fet­tosec­ond pulses at gi­gawatt power lev­els at a wave­length of 1.5 nm is gen­er­ated.  
 
WEPA01 Commissioning of a Photoinjector in HLS 331
 
  • Z.G. He, Q.K. Jia, B.G. Sun, X.H. Wang
    USTC/NSRL, Hefei, Anhui, People's Republic of China
  
  A BNL type pho­toin­jec­tor was in­stalled in HLS (Hefei Light Source) and com­mis­sion­ing work was car­ry­ing out in last months. The dark cur­rent was mea­sured when the high power test­ing of the gun was processed. The quan­tum ef­fi­ciency (QE) of the pho­to­cath­ode was mea­sured and stud­ied, the main pa­ra­me­ters of beam qual­ity such as elec­tric charge, trans­verse emit­tance and en­ergy were mea­sured and pre­sented in this paper.