1. H. Fukuzawa, Sang-Kil Son, K. Motomura, S. Mondal, K. Nagaya, S. Wada, X. -J. Liu, R. Feifel, T. Tachibana, Y. Ito, M. Kimura, T. Sakai, K. Matsunami, H. Hayashita, J. Kajikawa, P. Johnsson, M. Siano, E. Kukk, B. Rudek, B. Erk, L. Foucar, E. Robert, C. Miron, K. Tono, Y. Inubushi, T. Hatsui, M. Yabashi, M. Yao, R. Santra, and K. Ueda, “Deep inner-shell multiphoton ionization by intense x-ray free-electron laser pulses,” Phys. Rev. Lett. 110, 173005 (2013).
  2. H. Fukuzawa, K. Motomura, Sang-Kil Son, S. Mondal, T. Tachibana, Y. Ito, M. Kimura, K. Nagaya, T. Sakai, K. Matsunami, S. Wada, H. Hayashita, J. Kajikawa, X. -J. Liu, R. Feifel, P. Johnsson, M. Siano, E. Kukk, B. Rudek, B. Erk, L. Foucar, E. Robert, C. Miron, K. Tono, Y. Inubushi, T. Hatsui, M. Yabashi, M. Yao, R. Santra, and K. Ueda, “Sequential multiphoton multiple ionization of Ar and Xe by X-ray free electron laser pulses at SACLA” in XXVIII International Conference on Photonic, Electronic and Atomic Collisions (Lanzhou, China, July 24-30, 2013).
  3. K. Motomura, H. Fukuzawa, Sang-Kil Son, S. Mondal, T. Tachibana, Y. Ito, M. Kimura, K. Nagaya, T. Sakai, K. Matsunami, S. Wada, H. Hayashita, J. Kajikawa, X. -J. Liu, R. Feifel, P. Johnsson, M. Siano, E. Kukk, B. Rudek, B. Erk, L. Foucar, E. Robert, C. Miron, K. Tono, Y. Inubushi, T. Hatsui, M. Yabashi, M. Yao, R. Santra, and K. Ueda, “Sequential multiphoton multiple ionization of atomic argon and xenon irradiated by x-ray free-electron laser pulses at SACLA,” J. Phys. B: At. Mol. Opt. Phys. 46, 164024 (2013) [special issue on frontiers of free-electron laser science].
  4. Sang-Kil Son and Robin Santra, “Inner-shell multiphoton multiple ionization dynamics of xenon atoms by x-ray free-electron laser pulses” in DPG Spring Meeting of the Section AMOP (German Physical Society, Hanover, Germany, March 18-22, 2013) [oral presentation].