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Published on: July 27, 2018
Fine structure and ionization energy of the 1s2s2p 4P state of the helium negative ion He-
Liming Wang1, Chun Li2, Zong-Chao Yan3
1Department of Physics, Henan Normal University, Xinxiang, Henan, People's Republic of China 453007.
Abstract:
The fine structure and ionization energy of the 1s2s2p (4)P state of the helium negative ion He(-) are calculated in Hylleraas coordinates, including relativistic and QED corrections up to O(α(4)mc(2)), O((μ/M)α(4)mc(2)), O(α(5)mc(2)), and O((μ/M)α(5)mc(2)). Higher order corrections are estimated for the ionization energy. A comparison is made with other calculations and experiments. We find that the present results for the fine structure splittings agree with experiment very well. However, the calculated ionization energy deviates from the experimental result by about 1 standard deviation. The estimated theoretical uncertainty in the ionization energy is much less than the experimental accuracy.
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