Author: Chang, C.-H.
Paper Title Page
WEPO020 Magnetic Field Inspection and Analysis of Multipole Lattice Magnets using a Rotating-coil Measurement System* 2442
 
  • J.C. Jan, C.-H. Chang, Y.L. Chu, T.Y. Chung, C.-S. Hwang, C.Y. Kuo, F.-Y. Lin
    NSRRC, Hsinchu, Taiwan
  
  A pre­cise ro­tat­ing-coil mea­sure­ment sys­tem (RCS) was con­struct­ed to char­ac­ter­ize the field qual­i­ty and field cen­ter of mul­ti­pole lat­tice mag­nets of Tai­wan Pho­ton Source (TPS). The me­chan­i­cal cen­ter of mag­nets is de­ter­mined by the two ref­er­ences of the mag­net-feet and the RCS sys­tem is used to char­ac­ter­ize the field cen­ter. The lo­ca­tion of the mag­net­ic field cen­ter is quan­ti­ta­tive­ly ac­cu­rate to bet­ter than 20 mi­cro-me­ter in the hor­i­zon­tal di­rec­tion; the gran­ite sup­port height of the RCS sys­tem is ac­cu­rate with­in 5 mi­cro-me­ter after ar­ti­fi­cial pol­ish­ing. The mea­sure­ment re­pro­ducibil­i­ty of the field cen­ter was bet­ter than 10 mi­cro-me­ter when the mag­nets were re­in­stalled. The rel­a­tive ac­cu­ra­cy of the mul­ti­poles com­po­nents is bet­ter than 2×10-5. This paper re­ports the de­tails of the bench con­struc­tion and the unit com­po­si­tion. The field cen­ter with RCS mea­sure­ment will be com­pared and dis­cussed with the 3D-co­or­di­nate-mea­sur­ing ma­chine. The mul­ti­pole er­rors ob­tained from RCS will be com­pared with a Hall-probe mea­sure­ment sys­tem.  
 
THPC176 Progress in Insertion Devices for TPS in Phase I 3314
 
  • C.H. Chang, C.-H. Chang, J.C. Huang, C.-S. Hwang, C.K. Yang
    NSRRC, Hsinchu, Taiwan
  
  Tai­wan Pho­ton Source (TPS) with beam en­er­gy 3 GeV and beam cur­rent 500 mA is a third-gen­er­a­tion syn­chrotron ra­di­a­tion fa­cil­i­ty of medi­um en­er­gy. In the ini­tial com­mis­sion­ing stage of TPS, the ma­chine will be equipped with ten in­ser­tion de­vices (ID) and serve seven beam­lines in phase I. Of these, three long straight sec­tions con­fig­ured as a dou­ble-min­i­mum betay func­tion lat­tice de­sign with min­i­mized beam in­flu­ence of emit­tance are used for the in­stal­la­tion of a pair of in­ser­tion de­vices in a straight sec­tion, two un­du­la­tors of AP­PLE-II type and four in-vac­u­um un­du­la­tors (IU), to pro­duce great bril­liance and co­her­ent X-rays with great flux. The de­tails of these in­ser­tion de­vices are ex­plained here­in.  
 
THPC177 Field Correction Results from NSRRC Elliptically Polarized Undulator 46 3317
 
  • J.C. Huang, C.-H. Chang, C.-S. Hwang, C. JunTune, F.-Y. Lin
    NSRRC, Hsinchu, Taiwan
  
  El­lip­ti­cal­ly po­lar­ized un­du­la­tor (EPU) is a com­mon in­ser­tion de­vice to use in stor­age ring in order to pro­vide cir­cu­lar po­lar­iza­tion. The field cor­rec­tion is an es­sen­tial step for EPU con­struc­tion, and it can pre­vent the pho­ton flux re­duc­tion from idea case and elec­tron beam tra­jec­to­ry and exit angle from EPU. The con­ven­tion­al field cor­rec­tion method is te­dious works and strong­ly based on ex­pe­ri­ences. An ini­tial state of NSRRC EPU46 has phase error over 40 de­grees, and many dif­fi­cul­ties on field cor­rec­tion to re­duce the phase error under 5 de­grees. This paper will de­scribe the de­tailed mag­net­ic field cor­rec­tion pro­cess and prac­ti­cal re­sults from in NSRRC EPU.