Relativity, electron correlation and QED effects in the 1s2s²²S_1/2state of highly charged Li-like ions

Abstract

On the basis of a multiconfiguration Dirac–Fock method, a systematic study has been carried out for the decay process of the 1s2s2 2S1/2 state of Li-like ions. It is found that the decay properties of these states are quite different along the isoelectronic sequence: for low-Z ions up to Z = 30, the Auger decay channel is dominant; for medium-Z ions up to Z = 80, a two-electron one-photon radiative decay caused by a strong electron correlation becomes a competitive channel; and for very heavy ions about Z = 90, the magnetic dipole radiative decay becomes important too. In addition, the QED contributions to the excitation energy and the contributions from the Breit interaction to the Auger decay rates are stressed for heavy ions in particular.

Theoretical study of the KLL dielectronic recombination for highly charged iodine ions

“…It is obvious that the QED and Breit effects are very sensitive to the inner-shell excitations. The reason is that following the transfer of the inner 1s electron to a higher orbital, the strong orbital relaxation happened, which is consistent with our previous study for high-Z ions [19].…”

Irreducible tensor form of the relativistic corrections to the M1 transition operator

“…On the basis of a multiconfiguration Dirac-Fock method, a systematic study has been carried out for the decay process of the 1s2s 2 2 S 1/2 state of Li-like ions to discuss the balance between the Auger decay channel, the two-electron one-photon (TEOP) and M1 radiative decay modes [94]. Radiative rates are calculated for E1,M1,E2,M2 transitions in Cl-like Fe X [95] and in Boron-like to F-like Kr ions [96], using the GRASP code.…”

Relativistic configuration-interaction calculation of energy levels of core-excited states in lithiumlike ions: Argon through krypton

“…First accurate theoretical data on the core-excited states of lithium-like ions were obtained by Vainstein and Safronova within the 1/Z-expansion method [17]. Later, these states were addressed within the multiconfigurational Dirac-Fock approach [18][19][20] and, more recently, within the relativistic many-body perturbation theory [21]. In the present work, we employ the configuration-interaction (CI) method to obtain accurate values for the Dirac-Coulomb-Breit energies, including the nuclear recoil contribution and the frequencydependent Breit correction.…”