SYSTEMATICS OF X-RAY TRANSITION ENERGIES FOR HIGH-Z ATOMS

Abstract
Experimental and theoretical x-ray transition energies are precisely estimated and compared for 40<Z<100. All allowed and forbidden intervals for the n=1 to n=2, 3 levels are determined. The experimental values are derived from absolute wavelength measurements of Kα and Kβ transitions and from L series x-ray measurements. The theoretical values are obtained using a multiconfiguration Dirac-Fock code with some modifications in the Lamb shift calculations. Comparison between experiment and theory for Z<85 now provides a more coherent qualitative picture : (1) for the 1s^-1→2s^-1, 1s^-1→3s^-1, and 1s^-1→3p^-1 transitions, experimental energies are 5-10 eV larger, consistent with the magnitude and sign of the level shifts resulting from pair correlation and configuration mixing with Coster-Kronig and Auger transitions which were not included in the theory and (2) for the 1s¹→2p^-1 and 1s^-1→3d^-1 transitions, experimental energies are ≈ 3 eV larger, of which ≈ 1.5 eV can be attributed to pair correlation leaving ≈ 1.5 eV to higher order effects not included in our theory.