Fine structure of helium and light helium-like ions
نویسندگان
چکیده
Calculational results are presented for the fine-structure splitting of the 2P state of helium and helium-like ions with the nuclear charge Z up to 10. Theoretical predictions are in agreement with the latest experimental results for the helium fine-structure intervals as well as with the most of the experimental data available for light helium-like ions. Comparing the theoretical value of the 2P0 − 2P1 interval in helium with the experimental result [T. Zelevinsky et al. Phys. Rev. Lett. 95, 203001 (2005)], we determine the value of the fine-structure constant α with an accuracy of 31 parts per billion.
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