The two-time Green's Function and screened Self-Energy for two-electron quasi-degenerate States

E. -O. Le Bigot; P. Indelicato; V. M. Shabaev

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The two-time Green's Function and screened Self-Energy for two-electron quasi-degenerate States

E. -O. Le Bigot·P. Indelicato·V. M. Shabaev

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Abstract

Precise predictions of atomic energy levels require the use of QED, especially in highly-charged ions, where the inner electrons have relativistic velocities. We present an overview of the two-time Green's function method; this method allows one to calculate level shifts in two-electron highly-charged ions by including in principle all QED effects, for any set of states (degenerate, quasi-degenerate or isolated).

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E. -O. Le Bigot, P. Indelicato, V. M. Shabaev. 2000-12-01. The two-time Green's Function and screened Self-Energy for two-electron quasi-degenerate States. https://arxiv.org/abs/physics/0012001

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