Ground-state hyperfine structure of H-, Li-, and B-like ions in the intermediate-Z region (original) (raw)

Systematic model calculations of the hyperfine structure in light and heavy ions

Canadian Journal of Physics, 2002

Systematic model calculations are performed for the magnetization distributions and the hyperfine structure (HFS) of light and heavy ions with a mass close to A ∼ 6 208 235 to test the interplay of nuclear and atomic structure. A high-precision measurement of lithium-isotope shifts (IS) for suitable transition, combined with an accurate theoretical evaluation of the mass-shift contribution in the respective transition, can be used to determine the root-mean-square (rms) nuclear-charge radius of Li isotopes, particularly of the halo nucleus Li. An experiment of this type is currently underway at GSI in Darmstadt and ISOLDE at CERN. However, the field-shift contributions between the different isotopes can be evaluated using the results obtained for the charge radii, thus casting, with knowledge of the ratio of the HFS constants to the magnetic moments, new light on the IS theory. For heavy charged ions the calculated n-body magnetization distributions reproduce the HFS of hydrogen-like ions well if QED contributions are suppressed. Ab-initio calculations of the HFS of 209 Bi 80 + were performed to analyse this surprising result. Here, the boiling of the QED vacuum gives an important contribution to the HFS, thus modifying the theoretical results of other models. The investigations performed have initiated detailed studies of the structure of lithium-like ions heavier then bismuth, to obtain predictions for the experiments on uranium, which are proposed at PHELIX-XRL. PACS Nos.: 31.15Pf, 31.30Jv, 32.10Hq, 21.10GV, 21.10FT, 21.60+n Résumé : Nous avons fait des calculs théoriques systématiques des distributions de magnétisation et HFS (structure hyperfine) dans des ions légers et lourds, autour des masses A ∼ 6 208 235 de façon à vérifier le rôle relatif des structures atomique et nucléaire. Une mesure de haute précision du déplacement isotopique (IS) de certaines transitions dans le Li peut être couplée à une évaluation théorique précise du déplacement dû à la masse dans ces transitions, afin de déterminer la racine quadratique moyenne (rms) du rayon de la charge-nucléaire des isotopes de Li, en particulier du noyau à halo 11 Li. Une expérience de ce type est en cours au GSI et à ISOLDE, CERN. Cependant, la contribution due au

Evaluation of the screened QED corrections to thegfactor and the hyperfine splitting of lithiumlike ions

Physical Review A, 2010

The screened QED corrections of the first orders in α and 1/Z to the g factor and the hyperfine splitting of lithiumlike ions are evaluated within ab initio quantum electrodynamical approach. The complete gaugeinvariant set of the two-electron self-energy diagrams in the presence of the magnetic field and a dominant part of the two-electron vacuum-polarization diagrams are calculated. The most accurate values of the g factor of Li-like lead and uranium are presented. The theoretical prediction for the specific difference of the hyperfine splittings of Hand Li-like bismuth is improved.

A comparative study of finite nucleus models for low-lying states of few-electron high-Z atoms

Chemical Physics Letters, 2000

We studied low-lying states of lithium-like and beryllium-like ions with Z s 80 and 100 F Z F 120 for differential effects due to variation of the nuclear charge density distribution. The latter was represented by exponential, Gauss-type, and Fermi-type models, standardized to a common rms radius. Numerical Hartree-Fock and Dirac-Fock-Coulomb calculations were performed. Changes in total energies due to the use of different models become increasingly important for high Z in relativistic approaches. Different models may even lead to different sequences of atomic states, and thus energy differences between those states may vary by an order of magnitude. q

Hyperfine structure calculations for inner atomic levels

Journal of Physics B: Atomic, Molecular and Optical Physics, 1995

The results of Hmree-Fock-Dimc numerical calculations are given far the magnetic dipole and electric quadrupole hyperfine constants for the K and Lt-UI shells for all Z from 2 = 1&100. A comparison is made with results obtained with simple analytic formulae for the case of hydrogen-like ions with a simple screening and nuclear finite-sire corrections taken into account. Formulae are given for the atomic inner-shell hyperfine structure in the form suitable to calculate the hyperfine shifls of atomic states, excited in different processes. such as electron capture or an internal conversion.

Ground-state hyperfine splitting of high-Zhydrogenlike ions

Physical Review A, 1997

The ground state hyperfine splitting values of high Z hydrogenlike ions are calculated. The relativistic, nuclear and QED corrections are taken into account. The nuclear magnetization distribution correction (the Bohr-Weisskopf effect) is evaluated within the single particle model with the g S-factor chosen to yield the observed nuclear moment. An additional contribution caused by the nuclear spin-orbit interaction is included in the calculation of the Bohr-Weisskopf effect. It is found that the theoretical value of the wavelength of the transition between the hyperfine splitting components in 165 Ho 66+ is in good agreement with experiment.

Nuclear and Electron Polarization Contributions to the HFS of Hydrogen- and Lithium-like Ions

Hyperfine Interactions, 2000

The Dynamic Correlation Model (DCM) has been used to calculate nuclear ground-state wave functions of nuclei with one particle/hole in the closed shells. The strong mixing amplitudes between the valence particle/hole and the intrinsic vacuum states (valence hole coupled to core excitations) characterize the dynamic calculations of the hyperfine-structure splitting energy of the hydrogenlike ions which are in good agreement with measured values if the QED corrections are neglected. New experiments on the hyperfine-structure splitting energies of lithium-like ions could help in clarifying this still open point.

Transition energy and lifetime for the ground-state hyperfine splitting of high-Zlithiumlike ions

Physical Review A, 1998

The ground state hyperfine splitting values and the transition probabilities between the hyperfine structure components of high Z lithiumlike ions are calculated in the range Z = 49 − 83. The relativistic, nuclear, QED and interelectronic interaction corrections are taken into account. It is found that the Bohr-Weisskopf effect can be eliminated in a combination of the hyperfine splitting values of the hydrogenlike and lithiumlike ions of an isotope. This gives a possibility for testing the QED effects in a combination of the strong electric and magnetic fields of the heavy nucleus. Using the experimental result for the 1s hyperfine splitting in 209 Bi 82+ , the 2s hyperfine splitting in 209 Bi 80+ is calculated to be ∆E = 0.7969(2) eV.

Hyperfine splitting in heavy ions with the nuclear magnetization distribution determined from experiments on muonic atoms

Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms - NUCL INSTRUM METH PHYS RES B, 2005

The hyperfine splitting in hydrogenlike 209Bi, 203Tl, and 205Tl is calculated with the nuclear magnetization determined from experimental data on the hyperfine splitting in the corresponding muonic atoms. The single-particle and configuration-mixing nuclear models are considered. The QED corrections are taken into account for both electronic and muonic atoms. The obtained results are compared with other calculations and with experiment.