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Development of the Beamline Front End at the Pohang Light Source(PLS)-II

The third-generation synchrotron radiation accelerator has been providing beams to users since 1995 and have been made to upgrade the performances of the accelerators and the experimental devices. For that reason, the PLS-II was started in 2009 as a three-year project. An important feature is the extension of the ID (insertion device) beamline and the efficient placement of the storage ring magnet structure. The overall structure of the beamline as well as the length and structure of the front end had to be changed to expand the ID beamline. Also, the safety of many vacuum parts that would be exposed to the large heat due to the increase in the beam energy was firstly considered in the design, and an analysis was performed in parallel. This paper describes the overall structure of the front end, including the design and analysis of the vacuum components in the Pohang Light Source(PLS)-II beamline.