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Two-time Green function method in quantum electrodynamics of high-Z few-electron atoms

V. M. Shabaev
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Abstract

The two-time Green function method in quantum electrodynamics of high-Z few-electron atoms is described in detail. This method provides a simple procedure for deriving formulas for the energy shift of a single level and for the energies and wave functions of degenerate and quasi-degenerate states. It also allows one to derive formulas for the transition and scattering amplitudes. Application of the method to resonance scattering processes yields a systematic theory for the spectral line shape. The practical ability of the method is demonstrated by deriving formulas for the QED and interelectronic-interaction corrections to energy levels and transition and scattering amplitudes in one-, two-, and three-electron atoms. Numerical calculations of the Lamb shift, the hyperfine splitting, the bound-electron g factor, and the radiative recombination cross section in heavy ions are also reviewed.

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V. M. Shabaev. 2001-10-30. Two-time Green function method in quantum electrodynamics of high-Z few-electron atoms. https://doi.org/10.1016/s0370-1573(01)00024-2

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