Author: Park, S.J.
Paper Title Page
MOICNO02
 Control of Electron Beam Longitudinal Phase Space With a Novel Compact De-chirper for PAL-XFEL  
 
  • H.-S. Kang, M.S. Chae, T. Ha, J.H. Hong, W.W. Lee, S.J. Park, H. Yang
    PAL, Pohang, Kyungbuk, Republic of Korea
  
  The PAL-XFEL adopts a de-chirper system to remove the residual beam chirps with wakefield in corrugated pipes for the soft X-ray FEL line which is branched at 3 GeV point of the 10-GeV linac and does not have enough length of accelerating structures. The corrugated structure which is about 20 m long is designed to have the rectangular geometry and adjust the gap from 2 to 30 mm. We carried out the elegant code simulations using the wake formulas of G. Stupakov and K. Bane for the rectangular geometry to find the optimum parameters of corrugation using longitudinal wakes as well as to find the tolerance of vertical offset using transverse wakes. A 1-m long test de-chirper module is being designed and will be tested experimentally in July 2013 at the injector test facility in Pohang Accelerator Laboratory, which is a collaborative R&D with LBNL and SLAC.
Recommended by Zhirong Huang 		 
slides icon Slides MOICNO02 [10.661 MB]  
 
TUPSO28 Development of Photocathode RF-gun at PAL 279
 
  • J.H. Hong, J.H. Han, H.-S. Kang, Y.W. Parc, S.J. Park, Y.J. Park
    PAL, Pohang, Kyungbuk, Republic of Korea
  • I.S. Ko
    POSTECH, Pohang, Kyungbuk, Republic of Korea
  
  We are developing two types of S-band photocathode RF-guns for the X-ray free electron laser (XFEL) at Pohang Accelerator Laboratory (PAL). One is a 1.6-cell RF-gun with a dual side coupler and two pumping ports. This RF-gun is similar to the earlier guns developed at PAL. The other one is a 1.5-cell RF-gun with a coaxial coupler and a cathode preparation system. This RF-gun is similar to the DESY-type L-band RF-gun. We have designed and fabricated two types of RF-guns. In this paper we introduce and compare two different RF-guns.