Relativistic effect on x-ray multiphoton ionization dynamics of xenon atoms

Koudai Toyota, Sang-Kil Son, and Robin Santra

[BibTeX]http://www.dpg-verhandlungen.de/year/2016/conference/hannover/part/a/session/39/contribution/3

In this talk, we further investigate the previous experimental results on charge state distribution of Xe created by X-ray free-electron laser (XFEL) pulses at 5.5 keV, which was conducted at SACLA in Japan [1]. It was found that the theoretical yields for highly charged ionic states clearly underestimate the experimental results. It was considered that these come from non relativistic treatment in theory and lack of shake-off mechanism [1]. We recently have implemented relativistic energy corrections, within perturbative approach, into our computer code, XATOM. The relativistic energy corrections introduce several effects in multiphoton multiple ionization dynamics induced by XFEL pulses. First, some Coster-Kronig channels open, which are energetically forbidden in non relativistic treatment. Second, our preliminary calculations show that a combination of relativistic treatment and resonant excitation may enhance ionization. We will present our formulation and numerical results compared with experimental data. [1] H. Fukuzawa, S.-K. Son et al., Phys. Rev. Lett. 110. 173005 (2013).

Tags: Xe, relativity, XATOM, XFEL, CFEL, DESY