Author: Han, J.H.
Paper Title Page
WEB02 Beam Operation of the PAL-XFEL Injector Test Facility 615
  • J.H. Han, S.Y. Baek, M.S. Chae, H. J. Choi, T. Ha, J.H. Hong, J. Hu, W.H. Hwang, S.H. Jung, H.-S. Kang, C. Kim, C.H. Kim, I.Y. Kim, J.M. Kim, S.H. Kim, I.S. Ko, H.-S. Lee, J. Lee, S.J. Lee, W.W. Lee, C.-K. Min, G. Mun, D.H. Na, S.S. Park, S.J. Park, Y.J. Park, Y.G. Son, H. Yang
    PAL, Pohang, Kyungbuk, Republic of Korea
  The Pohang Accelerator Laboratory X-ray Free electron Laser (PAL-XFEL) project was launched in 2011. This project aims at the generation of X-ray FEL radiation in a range of 0.1 to 10 nm for photon users with a bunch repetition rate of 60 Hz. The machine consists of a 10 GeV normal conducting S-band linear accelerator and five undulator beamlines. The linac and two undulator beamlines will be constructed by the end of 2015 and first FEL radiation is expected in 2016. As a part of preparation for the project, an Injector Test Facility was constructed in 2012. Since December 2012, beam commissioning is being carried out to find optimum operating conditions and to test accelerator components including RF, laser, diagnostics, magnet, vacuum and control. We present the status of beam commissioning and components tests at the test facility.  
slides icon Slides WEB02 [10.249 MB]  
THP011 Beam Measurement of Photocathode RF-gun for PAL-XFEL 699
  • J.H. Hong, M.S. Chae, J.H. Han, H.-S. Kang, C.-K. Min, S.J. Park, Y.J. Park
    PAL, Pohang, Kyungbuk, Republic of Korea
  • I.S. Ko
    POSTECH, Pohang, Kyungbuk, Republic of Korea
  The Injector Test Facility (ITF) at Pohang Accelerator Laboratory (PAL) was constructed to develop an injector for the PAL X-ray free-electron laser (PAL-XFEL) project. The PAL-XFEL design requires the injector to produce an electron beam with a slice emittance of 0.4 mm-mrad at the charge of 200 pC. A 4-hole type RF-gun has been successfully fabricated and tested at ITF. In this paper we report the recent beam-measurement results using the RF-gun at ITF. Emittance measurements have been carried out by changing laser and RF parameters.  
THP012 Error Analysis for Linac Lattice of Hard X-ray FEL Line in PAL-XFEL* 703
  • H. Yang, J.H. Han, H.-S. Kang, I.S. Ko
    PAL, Pohang, Kyungbuk, Republic of Korea
  Funding: *This work was supported by MSIP, Korea.
PAL-XFEL consists of the hard x-ray line for 0.06 – 1-nm FEL and the soft x-ray line for 1 – 10-nm FEL. The linac of hard x-ray line is designed to generate 10-GeV, 200-pC, and 3-kA electron beam. It consists of S-band accelerating columns, an X-band linearizer, three bunch compressors (BC). We conduct error simulation in order to evaluate the tolerances of machine parameters and alignments. First, the machine tolerances and beam jitter levels are calculated in the simulations with dynamic errors and we find out the optimized lattice to satisfy the target tolerance of machine. Second, we conduct simulations with misalignment. We quantify the emittance dilution by misalignments, especially those of BCs. In order to compensate the misalignments, the methods of beam correction like Beam Based Alignment (BBA) are presented and the effects of emittance improvements are calculated.
poster icon Poster THP012 [0.736 MB]  
THP013 Slice Emittance Measurement using RF Deflecting Cavity at PAL-XFEL ITF 707
  • J. Lee
    POSTECH, Pohang, Kyungbuk, Republic of Korea
  • J.H. Han, J.H. Hong, I.S. Ko, S.J. Park
    PAL, Pohang, Kyungbuk, Republic of Korea
  One of key characteristic for operating PAL-XFEL is the time-dependent transverse properties of a bunch, slice emittance. To achieve the design FEL performance of PAL-XFEL a slice emittance of 0.4 mm mrad at 0.2 nC is required. An Injector Test Facility (ITF) was constructed to study beam properties. In addition to projected emittance measurement, slice emittance measurement is being done using a transverse RF deflecting cavity. We presents results of slice emittance measurement at ITF and future plan for the optimization of operating condition.