A5087400919- Atomic and Molecular Physics
- Nuclear physics research studies
- Muon and positron interactions and applications
- Advanced Chemical Physics Studies
- Particle accelerators and beam dynamics
- Quantum Chromodynamics and Particle Interactions
- Scientific Measurement and Uncertainty Evaluation
- Particle physics theoretical and experimental studies
- X-ray Spectroscopy and Fluorescence Analysis
- Cold Atom Physics and Bose-Einstein Condensates
- Advanced Frequency and Time Standards
- Atomic and Subatomic Physics Research
- Mass Spectrometry Techniques and Applications
- Advanced NMR Techniques and Applications
- Advanced X-ray Imaging Techniques
- Crystallography and Radiation Phenomena
- Radioactive Decay and Measurement Techniques
- Nuclear Physics and Applications
- Electron and X-Ray Spectroscopy Techniques
- High-Energy Particle Collisions Research
- Neutrino Physics Research
- Astrophysics and Cosmic Phenomena
- Astrophysical Phenomena and Observations
- Relativity and Gravitational Theory
- Laser-Plasma Interactions and Diagnostics
Max Planck Institute for Nuclear Physics
2016-2025
Max Planck Society
2014-2020
St Petersburg University
2004-2010
Technische Universität Dresden
2007
A possibility for a determination of the fine structure constant in experiments on bound-electron g-factor is examined. It found that studying specific difference g-factors B- and H-like ions same spinless isotope Pb region to currently accessible experimental accuracy 7 x 10(-10) would lead an which better than accepted value. Further improvements theoretical could provide value several times more precise one.
We measure optical spectra of Nd-like W, Re, Os, Ir, and Pt ions particular interest for studies a possibly varying fine-structure constant. Exploiting characteristic energy scalings we identify the strongest lines, confirm predicted 5s-4f level crossing, benchmark advanced calculations. infer two possible values M2/E3 E1 transitions in Ir^{17+} that have highest sensitivity to variation constant among stable atomic systems. Furthermore, determine energies proposed frequency standards...
Helium-3 has nowadays become one of the most important candidates for studies in fundamental physics [1, 2, 3], nuclear and atomic structure [4, 5], magnetometry metrology [6] as well chemistry medicine [7, 8]. In particular, $^3$He magnetic resonance (NMR) probes have been proposed a new standard absolute [6, 9]. This requires high-accuracy value moment, which, however, so far determined only indirectly with relative precision $12$ parts per billon (p.p.b.) [10,11]. Here we investigate...
We have measured the ground-state $g$ factor of boronlike argon ${^{40}\mathrm{Ar}}^{13+}$ with a fractional uncertainty $1.4\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}9}$ single ion in newly developed Alphatrap double Penning-trap setup. The value $g=0.663\text{ }648\text{ }455\text{ }32(93)$ obtained here is agreement our theoretical prediction 0.663 648 12(58). latter accounting for quantum electrodynamics, electron correlation, and nuclear effects within state-of-the-art...
For more than 40 years, most astrophysical observations and laboratory studies of two key soft x-ray diagnostic 2p-3d transitions, 3C 3D, in Fe XVII ions found oscillator strength ratios f(3C)/f(3D) disagreeing with theory, but uncertainties had precluded definitive statements on this much studied conundrum. Here, we resonantly excite these lines using synchrotron radiation at PETRA III, reach, a millionfold lower photon intensities, 10 times higher spectral resolution, 3 smaller uncertainty...
One of the most enduring and intensively studied problems x-ray astronomy is disagreement state-of-the art theory observations for intensity ratio two Fe XVII transitions crucial value plasma diagnostics, dubbed 3C 3D. We unravel this conundrum at PETRA III synchrotron facility by increasing resolving power 2.5 times signal-to-noise thousandfold compared with our previous work. The Lorentzian wings had hitherto been indistinguishable from background were thus not modeled, resulting in a...
Abstract Tin is the chemical element with largest number of stable isotopes. Its complete proton shell, comparable closed electron shells in chemically inert noble gases, not a mere precursor to extended stability; since protons carry nuclear charge, their spatial arrangement also drives electromagnetism. We report high-precision measurements electromagnetic moments and isomeric differences charge radii between lowest 1/2 + , 3/2 11/2 − states 117–131 Sn, obtained by collinear laser...
There is renewed interest in studies of muonic atoms, which may provide detailed information on nuclear structure. A major limiting factor the interpretation measurements polarization contribution. We propose a method to determine this contribution hyperfine structure atoms from combination theory and experiment for hydrogenlike ions atoms. Applying ^{203,205}Tl ^{209}Bi, there are H-like ion atom experimental data, we find that these systems small place limit its size less than 10% total...
The hyperfine splitting of the ground state H-, Li-, and B-like ions is investigated in details within range nuclear numbers $Z=7--28$. rigorous QED approach together with large-scale configuration-interaction Dirac-Fock-Sturm method are employed for evaluation interelectronic-interaction contributions first higher orders $1∕Z$. screened corrections evaluated to all $\ensuremath{\alpha}Z$ utilizing an effective potential approach. influence magnetization distribution taken into account...
The hyperfine splitting of the 5g→4f transitions in muonic 185,187Re has been measured using high resolution purity germanium detectors and compared to state-of-the-art atomic theoretical predictions. spectroscopic quadrupole moment extracted modern fitting procedures values available literature obtained from x rays natural rhenium. nuclear are 2.07(5) b 1.94(5) b, respectively for 185Re 187Re.1 MoreReceived 27 November 2019Accepted 21 February...
A long-standing problem of fine-structure anomalies in muonic atoms is revisited by considering the splittings $\mathrm{\ensuremath{\Delta}}2p={E}_{2{p}_{3/2}}\ensuremath{-}{E}_{2{p}_{1/2}}$ $^{90}\mathrm{Zr}$, $^{120}\mathrm{Sn}$, and $^{208}\mathrm{Pb}$ $\mathrm{\ensuremath{\Delta}}3p={E}_{3{p}_{3/2}}\ensuremath{-}{E}_{3{p}_{1/2}}$ $^{208}\mathrm{Pb}$. State-of-the-art techniques from both nuclear atomic physics are brought together order to perform most comprehensive date calculations...
In the experiment, <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi>g</a:mi></a:math> factor of boronlike <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:mrow><c:mmultiscripts><c:mrow><c:msup><c:mrow><c:mi>Sn</c:mi></c:mrow><c:mrow><c:mn>45</c:mn><c:mo>+</c:mo></c:mrow></c:msup></c:mrow><c:mprescripts/><c:none/><c:mrow><c:mn>118</c:mn></c:mrow></c:mmultiscripts></c:mrow></c:math> has been measured with a 0.5 ppb uncertainty. This is first...
A discrepancy between atomic theory and laboratory astrophysics experiments measuring the x-ray emission lines from highly charged Iron ions can be resolved by including nonlinear dynamical light-atom interactions.
The nuclear shape correction to the $g$ factor of a bound electron in $1S$ state is calculated for number nuclei range charge numbers from $Z=6$ up $Z=92$. leading relativistic deformation has been derived analytically, and also its influence on one-loop quantum electrodynamic terms evaluated. We show corrections become significant mid-$Z$ ions very heavy elements even reach ${10}^{\ensuremath{-}6}$ level.
Two-loop self-energy corrections to the bound-electron $g$ factor are investigated theoretically all orders in nuclear binding strength parameter $Z\alpha$. The separation of divergences is performed by dimensional regularization, and contributing diagrams regrouped into specific categories yield finite results. We evaluate numerically loop-after-loop terms, remaining treating Coulomb interaction electron propagators up first order. results show that such two-loop terms mandatory take...
The nuclear-polarization corrections to the energy levels of highly charged ions are systematically investigated leading order in fine-structure constant. To this end, notion effective photon propagators with insertions is employed, where nuclear excitation spectrum calculated by means Hartree-Fock-based random-phase approximation. Skyrme force used describe interaction between nucleons, and model dependence analyzed. order, formalism predicts two contributions given vacuum-polarization...
The transition energies of the two <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mrow><a:mn>1</a:mn><a:mi>s</a:mi></a:mrow></a:math> core-excited soft x-ray lines (dubbed <b:math xmlns:b="http://www.w3.org/1998/Math/MathML"><b:mi>q</b:mi></b:math> and <c:math xmlns:c="http://www.w3.org/1998/Math/MathML"><c:mi>r</c:mi></c:math>) from <d:math...
The fully relativistic theory of the $g$ factor hydrogenlike ions with nonzero nuclear spin is considered. hyperfine-interaction correction to atomic calculated for both point and extended charge-distribution models nuclei. Both magnetic dipole electric quadrupole interactions are taken into account. This combined corrections resulting from QED, recoil, size, obtain theoretical high-precision values spin. results can be used a precise determination moments experiments.
The green coronal line at 530.3 nm was first observed during the total solar eclipse of 1869. Once identified as emitted by Fe xiv, it became clear that this highly charged ion typical for range temperatures found in plasmas, stellar winds, outflows, and accretion disks. Under these conditions high ionization, strongest transitions are X-ray, extreme ultraviolet, ultraviolet wavelength range, with only few optical lines. For so-called forbidden lines, scarce laboratory data is available,...
When collecting spectroscopic data on at least four isotopes, nonlinearities in the King plot are a possible sign of physics beyond standard model. In this work, an improved approach to search for hypothetical new interactions with isotope-shift spectroscopy few-electron ions is presented. Careful account taken small nuclear corrections energy levels and gyromagnetic factors, which cause deviations from linearity within model hence source confusion. approach, experimental nonlinearity not...
We present the most accurate up-to-date theoretical values of $2{p}_{1∕2}\text{\ensuremath{-}}2s$ and $2{p}_{3∕2}\text{\ensuremath{-}}2s$ transition energies ground-state hyperfine splitting in ${\mathrm{Sc}}^{18+}$. All two- three-electron contributions to energy up two-photon level are treated framework bound-state QED without $\ensuremath{\alpha}Z$ expansion. The interelectronic interaction beyond is taken into account by means large-scale configuration-interaction Dirac-Fock-Sturm...
Precision calculations of the fine and hyperfine structure muonic atoms are performed in a relativistic approach results for $^{205}\mathrm{Bi}, ^{147}\mathrm{Sm}$, $^{89}\mathrm{Zr}$ presented. The due to magnetic dipole electric quadrupole splitting is calculated first-order perturbation theory, using extended nuclear charge current distributions. leading correction from quantum electrodynamics, namely vacuum polarization Uehling approximation, included as potential directly Dirac...
Numerous few-electron atomic systems are considered which can be used effectively for observing a potential variation of the fine-structure constant $\ensuremath{\alpha}$ and electron-proton mass ratio ${m}_{e}/{m}_{p}$. We examine optical magnetic dipole transitions between hyperfine-structure components in heavy highly charged H-like Li-like ions with observably high sensitivity to The experimental spectra proposed consist strong single line, simplifies significantly data analysis shortens...
We investigated Pm-, Nd-, and Pr-like spectra in the extreme ultra-violet region around 20 nm of Pt, Ir, Os, Re (Z = 78–75) produced Heidelberg electron beam ion trap. Identification transitions was supported by several theoretical calculations, including collisional radiative modeling observed spectra. Special attention is given to identifications alkaline-like – resonance lines promethium-like highly charged ions. Previous these have been tentative at best due disagreements with theory...
QED corrections to the $g$ factor of Li-like and B-like ions in a wide range nuclear charges are presented. Many-electron contributions as well radiative effects on one-loop level calculated. Contributions resulting from interelectronic interaction, self-energy effect, most terms vacuum-polarization effect evaluated all orders coupling strength $Z\ensuremath{\alpha}$. Uncertainties size effects, numerical computations, uncalculated discussed.