Author: Cho, M.-H.
Paper Title Page
MOPEA049 The First Experience of PLS-II Operation 190
  • S.H. Nam, M.-H. Cho, J.Y. Huang, C.D. Park, S. Shin
    PAL, Pohang, Kyungbuk, Republic of Korea
  Funding: Mministry of Education, Science and Technology (MEST) of Korea
One of recent major activities of the Pohang Accelerator Laboratory (PAL) in Korea has been PLS-II user operation. The PLS-II is a Korea’s only and brand new 3rd generation synchrotron radiation source that was upgraded from the 16-year-old PLS in 2011. The old PLS started user service from 1995 and shutdown on Dec. 10, 2010. The PLS-II has been open to users from March 2012 with upgraded performance. The performance parameters of the PLS-II are 5.8 nm-rad emittance, 3.0GeV beam energy, and 400mA beam current with the top-up injection. The unique feature of PLS-II will be the implementation of 20 insertion-devices in a compact double-bend-achromat storage ring of 280m-long circumference. Among 20 insertion-devices, 14 are in-vacuum undulators. The first year operation in 2012 will be successfully completed and the operational statistics will be summarized and discussed.
THPME026 First Results of the PAL-XFEL Prototype Undulator Measurements 3561
  • D.E. Kim, H.S. Han, Y.-G. Jung, H.-G. Lee, S.B. Lee, W.W. Lee, K.-H. Park, H.S. Suh
    PAL, Pohang, Kyungbuk, Republic of Korea
  • M.-H. Cho, I.S. Ko
    POSTECH, Pohang, Kyungbuk, Republic of Korea
  Pohang Accelerator Laboratory (PAL) is developing 10 GeV, 0.1 nm SASE based FEL for high power, short pulse X-ray coherent photon sources named PAL-XFEL. At the first stage PAL-XFEL needs two undulator lines for photon source. PAL is developing undulator magnetic structure based on EU-XFEL design. The hard X-ray undulator features 7.2 mm min magnetic gap, and 5.0 m magnetic length with maximum effective magnetic field larger than 0.908 T to achieve 0.1nm radiation at 10 GeV electron energy. A prototype for PAL-XFEL Xray undulator line is completed and the measurement, correction results are summarized.  
THPWA030 Design and Prototype Test of C-band Standing-wave Accelerating Structure to Enhance RF Phase Focusing 3690
  • H. Yang, M.-H. Cho, W. Namkung, S.-G. Shin
    POSTECH, Pohang, Kyungbuk, Republic of Korea
  • S.H. Kim
    ANL, Argonne, USA
  • J.-S. Oh
    NFRI, Daejon, Republic of Korea
  Funding: This research was financially supported by the MOTIV, KIAT and Dongnam Institute for Regional Program Evaluation through the Leading Industry Development for Economic Region
A C-band standing-wave accelerator for X-ray and electron beam sources of medical radiotherapy is designed and being fabricated. The accelerator system is to be operated in two modes, using the X-ray and electron beams. Because of the energy loss in electron mode, the accelerator is capable of producing 6-MeV, 100-mA electron beams with peak 2-MW RF power, and 7.5-MeV, 20 mA electron beams with peak 2.5-MW RF power. The beam radius at the end of column was < 0.5 mm without focusing magnets in PARMELA simulations, because the bunching cells are designed to enhance the RF phase focusing. Each cavity in the bunching and normal cells was designed by the MWS code to maximize the effective shunt impedance with 3.8% inter-cell coupling in normal cells. The dimensions of normal cells were determined by the low power RF test of prototype cells with 5711.06-MHz resonant frequency and 3.5% inter-cell coupling. In this paper, we present details of the accelerator design and prototype test.