Author: Cheng, C.M.
Paper Title Page
MOPPR050 Design and Analysis of EPU XBPM in TPS 894
  • A. Sheng, C.M. Cheng, C.K. Kuan
    NSRRC, Hsinchu, Taiwan
  • D. Shu
    ANL, Argonne, USA
  Several planer and elliptical polarized undulators (EPU) beam lines have been proposed and are to be built for Taiwan Photon Source (TPS) in National Synchrotron Research Center (NSRRC). Due to its complexity, with changing of vertical as well as horizontal deflection parameters (Kx and Ky), one finds that regular diamond bladed photon beam position monitor (XBPM) would not be sufficient to detect the center location of the undulator. A new conceptual design of EPU XBPM has been analyzed both in thermal as well as photon aspects. A prototype by taking advantage of fluorescent some of the diamond detectors has been designed and implemented in Taiwan Light Source (TLS) for testing. Some analysis and design scenarios are presented in this paper.  
WEPPD002 The Purifier System for Helium Cryogenic Plant in NSRRC 2498
  • H.C. Li, S.-H. Chang, C.M. Cheng, W.-S. Chiou, F. Z. Hsiao, T.F. Lin, C.P. Liu, H.H. Tsai
    NSRRC, Hsinchu, Taiwan
  A cryogenic adsorber is a purifier cooled with liquid nitrogen that is used to trap impurities from gaseous helium in the helium cryogenic system. The output purity can be decreased to less than 5 ppm and the dew point to -62 °C. The maximum rate of flow of each adsorber is 95 Nm3/h. We installed five cryogenic adsorbers in the cryogenic system and completed its testing in 2011; five additional cryogenic adsorbers will be installed in 2012. The configuration, installation, test results and operation of an cryogenic adsorber system are reported herein.
"cryogenic adsorber","purifier"
WEPPD003 Development of a Condenser for the Helium Phase Separator at NSRRC 2501
  • C.P. Liu, C.M. Cheng, F. Z. Hsiao, T.Y. Huang, H.H. Tsai
    NSRRC, Hsinchu, Taiwan
  A helium phase separator with a condenser is under fabrication and assembly at National Synchrotron Radiation Research Center (NSRRC). The objective of a helium phase separator with its condenser is to separate two-phase helium flow and to re-condense vaporized gaseous helium with a cryo-cooler of Gifford-McMahon type. This paper presents the design and fabrication of the condenser, a key component of the helium phase separator. A preliminary steady-state simulation of the efficiency of the helium condenser is also presented.
"Condenser","Rate of condensation"
WEPPD020 Vacuum System for TPS Booster 2540
  • C.M. Cheng, C.K. Chan, C.L. Chen, J.-R. Chen, G.-Y. Hsiung, S-N. Hsu, H.P. Hsueh
    NSRRC, Hsinchu, Taiwan
  The TPS booster is designed for lower beam emittance and 3GeV full energy injection ramped up from 150MeV. It is a synchrotron accelerator of 496.8m in circumference and located concentric with the electron storage ring in the same tunnel. The vacuum system for the booster is divided into six super periods and each has nine bending magnet chambers. The beam duct is made of thin stainless steel tube extruded to the elliptical cross section with inner diameters of 35 mm×20 mm and thickness of 0.7 mm. All the chambers will be supported on the inner wall of the tunnel. The straightness of the extruded thin chambers is controlled within 2.5 mm in 4 m length. The bending chamber is made by mechanical bending from the straight tube. All the beam ducts will be chemical cleaned prior to welding, with flanges or BPM chambers, to form the long chambers in the clean room before installation. The arrangement of vacuum pumps are distributed to fulfill an average pressure of <1×10-6 Pa. The detailed design and the construction status will be described in the paper.  
WEPPD021 Optimization of the Ultra-High Vacuum Systems for the 3 GeV TPS Synchrotron Light Source 2543
  • G.-Y. Hsiung, C.K. Chan, C.-C. Chang, C.L. Chen, J.-R. Chen, C.M. Cheng, Y.T. Cheng, S-N. Hsu, H.P. Hsueh, Huang, Y.T. Huang, I.C. Sheng, L.H. Wu, Y.C. Yang
    NSRRC, Hsinchu, Taiwan
  The Taiwan Photon Source (TPS), a 3 GeV synchrotron light source, provides an ultra-low emittance of electron beam and the consequent extremely high brightness of photons. The vacuum pressure along the beam duct should be ultra-high vacuum (UHV) and even lower for reduction of the impact to the beam from the gas scattering or ion trapping troubles. Most of the outgas comes from the photon stimulated desorption (PSD) back streaming from downstream absorbers during beam operation and large area surface outgas inside the beam duct as well. Due to the anticipate request of the smallest vertical aperture of beam ducts from various insertion devices and the lowest broadband impedance through all the vacuum chambers of electron storage ring, the inner structure design and the surface treatment of vacuum chambers as well as the constraint of the back stream PSD outgas from distributed absorbers and the pumping locations should be optimized to obtain a high quality UHV system for the high stable synchrotron light source through the long period of operation. The optimized design of the vacuum chambers for the TPS will be described.  
WEPPD022 Design of the Water-Cooling System for the Vacuum System of the TPS Storage Ring 2546
  • Y.C. Yang, C.K. Chan, J.-R. Chen, C.M. Cheng, G.-Y. Hsiung
    NSRRC, Hsinchu, Taiwan
  Taiwan Photon Source (TPS) was under construction since 2009. TPS vacuum system was designed in 10-10 torr level and gas load from synchrotron light was almost confined in bending chambers. A water cooling system was designed to protect vacuum equipment including vacuum chambers and absorbers to avoid melting down by synchrotron light. There are 3 cooling loops for aluminum chambers and 4 loops for cooper absorbers in one unit cell. One prototype for unit cell, including arrangement of control terminal, monitor of flow rate and temperature, and vibration from cooling system will be tested.  
WEPPD024 A Study of Vacuum Pressure in TPS Cells 2552
  • L.H. Wu, J.-R. Chen, C.M. Cheng, G.-Y. Hsiung, C.S. Huang, Huang, Y.T. Huang
    NSRRC, Hsinchu, Taiwan
  Recently, the type-2 and type-3 TPS cells are installed and pumped down into vacuum status. The pumping down curves of the type-2 and type-3cells, including R03, R06, R07, R10, and R11, are recorded after on-site welding and after assembling without leakage, individually. In the R03, R06, R07, R10 cells, the pumping down curve after assembling without leakage is a little higher than that after on-site welding. In those four cells, the pumping down curve after assembling all vacuum components and pumps is similar. However, in the R11 cell, it was found that the pumping down curve after assembling without leakage is almost along that of after on-site welding. The slope of pumping down curve near 1 hour in the R11 cell is -1.52, while that in the R10 cell is -1.39. It means that the vacuum pressure in the R11 cell is apparently improved. It is confirmed that the vacuum chambers are cleaned by the same process and the assembling components are similar. Besides, the photon stopper chambers are all pre-baked to 200 oC for the same time. We try to investigate the residual gas analysis (RGA) data to find the true reasons.