Abstract
Several parts that comprise the large scientific equipment should be installed and operated at precise three-dimensional location coordinates X, Y, and Z through survey and alignment to ensure their optimal performance. As time goes by, however, the ground uplifts and subsides, which changes the coordinates of the installed components and leads to alignment errors ΔX, ΔY, and ΔZ. As a result, the system parameters change, and the performance of the large scientific equipment deteriorates accordingly. Measuring the change in the locations of the systems comprising the large scientific equipment in real time would make it possible to predict alignment errors, locate any region with greater changes, realign components in the fast changing region and shorten the time of survey and alignment. For this purpose, a hydrostatic leveling sensor (HLS) with 0.2 μm resolution was installed and is operated in the PAL-XFEL building. In addition, a 2D wire position sensor (WPS) with a 0.1 μm resolution was installed and is operated in the undulator sections where measurements of the two-dimensional changes of the systems (vertical & horizontal) are necessary. This paper is designed to introduce the operating principle of the 2D WPS, the installation and operation of the WPS system, and the way in which the WPS system is utilized in order to ensure beam stability.
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Choi, H., Lee, S., Lee, HG. et al. 2D WPS System for Measuring the Location Changes in Real Time of PAL-XFEL Devices. J. Korean Phys. Soc. 73, 1034–1041 (2018). https://doi.org/10.3938/jkps.73.1034
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DOI: https://doi.org/10.3938/jkps.73.1034