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Achievement and prospect of the PAL-XFEL


The PAL-XFEL has demonstrated excellent timing stability and unprecedented peak brightness since its start of user service operation in June 2017. The 18-fs timing stability in the XFEL allows excellent pump-probe time-resolved experiments with low timing jitter. A self-seeding scheme enables us to produce a higher peak brightness of the XFEL with a narrow bandwidth. The plans for improving the capability of the PAL-XFEL as a user facility have been studied. The 2nd hard X-ray FEL line was designed to double the hard X-ray user’s beamtime, and polarization tunability will be implemented in the soft X-ray FEL line. It will allow more users to experience new science.

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This research has been supported by the Basic Science Research Program (Grant no. NRF-2021R1A2C3010748) through the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT of Korea.

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Correspondence to Heung-Sik Kang.

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Kang, HS. Achievement and prospect of the PAL-XFEL. J. Korean Phys. Soc. 80, 684–692 (2022).

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  • X-ray free-electron laser
  • Timing stability
  • Brightness
  • Self-seeding
  • Polarization
  • Attosecond