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Calculation of quasi-degenerate energy levels of two-electron ions

O. Yu. Andreev·L. N. Labzowsky·G. Plunien·G. Soff
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Abstract

Accurate QED calculations of the interelectron interaction corrections for the $(1s2p)2 {}^1 P_1$, $(1s2p)2 {}^3 P_1$ two-electron configurations for ions with nuclear charge numbers $10\le Z \le 92$ are performed within the line profile approach. Total energies of these configurations are evaluated. Employing the fully relativistic treatment based on the {$j$--$j$} coupling scheme these energy levels become quasi-degenerate in the region $Z\le 40$. To treat such states within the framework of QED we utilize the line profile approach. The calculations are performed within the Coulomb gauge.

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O. Yu. Andreev, L. N. Labzowsky, G. Plunien, G. Soff. 2003-12-17. Calculation of quasi-degenerate energy levels of two-electron ions. https://doi.org/10.1103/physreva.69.062505

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