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QED corrections in many-electron system

Energies (eV) of the 3s — 2 pz/2 transitions in Na-like to Al-like uranium [81], Na-1 is the 3s - 3p3/2 line. Mg-1 is the (3s )j=o - (3s3p3/2)./=i line. Al-1 is the (3s 3pi/2)./=i/2 -(3s3pi/23p3/2)j=i/2 line. W, CV and CC are valence-valence, core-valence and core-core contributions to the Coulomb energies, respectively. Bq and B are frequency-independent and frequency-dependent contributions to the Breit energies, respectively. [Pg.179]

For consistency with RCI calculations, we also use DKS potentials for screened QED calculations. DKS potentials have been shown in Ref. [77] to give very good QED results for high-Z Li-like and Be-like ions and they appear to work just as well for Na-like to Si-like uranium [81]. Typically, QED corrections to transition energies are carried out in a frozen-core approximation where contributions from the valence electrons are considered but not those from the core electrons which cancel exactly between the initial and final states. In [77] and [81], however, it was found that core-relaxation effects are important and that they can be accounted for by summing the differences in QED energies of the core electrons as calculated with two different DKS potentials specific to the electronic configurations of the initial and final states of the transition. [Pg.179]

An example of these QED calculations is shown in Table 11 where comparisons arc made between theory and experiment for the 3s — 3p3/2 transition energies in Na-like to Al-like uranium. In this table, RCI Coulomb energies are broken down into valence-valence (W), core-valence (CV) and core-core (CC) contributions, with the reference states taken to be consisted of the dominant n = 3 configurations of the atomic states. While CV results do not appear to be any larger than the CC results, that is largely due to cancellations between the initial and final states and CV contributions have to [Pg.179]

In conclusion, relativistic atomic structure calculations based on the MBPT and RCI methods are now accurate enough to make precision tests of QED theory in many-electron systems. Tests of parity non-conserving effects in heavy, neutral atoms have also been carried out and this topic is covered in another chapter of this book series. [Pg.181]

The work of WRJ was supported in part by NSF Grant No. PHY-0139928. The work of KTC and MHC were performed under the auspices of the U.S. Department of Energy by the University of California, Lawrence Livermore National Laboratory under Contract No. W-7405-Eng-48. [Pg.181]


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