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Direct Observation of the 2d3/2 - 2d5/2 Ground State Splitting in Xe9+



E Takacs, B Blagojevic, K Makonyi, E O. LeBigot, Csilla Szabo-Foster, Yong Sik Kim, John D. Gillaspy


We have used the NIST Electron Beam Ion Trap to observe a visible line at 598.30(13) nm that corresponds to the 4d9 2D3/2 - 4d9 2D5/2 magnetic dipole transition within the ground state configuration of Xe9+. We have found no evidence to support the claim by others that a line near this position originates from Xe31+. The comparison of the measured wavelength with previous indirect experimental values, and the dependence of the line intensity on the electron beam energy confirms the validity of the present identification. Our measured wavelength is in agreement with semi-empirical Hartree-Fock calculations but shows a discrepancy with ab initio MCDF calculations. We propose that the line may be useful as a diagnostic for EUV lithography light sources.
Physical Review A (Atomic, Molecular and Optical Physics)


EBIT, EUV lithography, highly charged ions, magnetic dipole transition, Multi-Configuration Dirac-Fock, visible spectroscopy


Takacs, E. , Blagojevic, B. , Makonyi, K. , LeBigot, E. , Szabo-Foster, C. , Kim, Y. and Gillaspy, J. (2006), Direct Observation of the <sup>2<sub></sub>d3/2</sup> - <sup>2<sub></sub>d5/2</sup> Ground State Splitting in Xe<sup>9+</sup>, Physical Review A (Atomic, Molecular and Optical Physics), [online],, (Accessed February 27, 2024)
Created May 17, 2006, Updated October 12, 2021