A5070941356- Atomic and Molecular Physics
- Mass Spectrometry Techniques and Applications
- Nuclear physics research studies
- Atomic and Subatomic Physics Research
- Cold Atom Physics and Bose-Einstein Condensates
- Particle accelerators and beam dynamics
- Advanced Frequency and Time Standards
- Advanced Chemical Physics Studies
- Radioactive Decay and Measurement Techniques
- Nuclear Physics and Applications
- Scientific Measurement and Uncertainty Evaluation
- Dark Matter and Cosmic Phenomena
- Particle physics theoretical and experimental studies
- Laser-Matter Interactions and Applications
- Particle Accelerators and Free-Electron Lasers
- Laser-induced spectroscopy and plasma
- Astronomical and nuclear sciences
- X-ray Spectroscopy and Fluorescence Analysis
- Magnetic confinement fusion research
- Quantum, superfluid, helium dynamics
- Quantum Chromodynamics and Particle Interactions
- Superconducting Materials and Applications
- Particle Detector Development and Performance
- Advanced NMR Techniques and Applications
- Ion-surface interactions and analysis
GSI Helmholtz Centre for Heavy Ion Research
2016-2025
Heidelberg University
2013-2023
Artemis (United States)
2015
Astrophysique Relativiste, Théories, Expériences, Métrologie, Instrumentation, Signaux
2015
Johannes Gutenberg University Mainz
1996-2011
Max Planck Institute for Nuclear Physics
2011
Helmholtz Institute Jena
2011
Technical University of Darmstadt
2000-2011
St Petersburg University
2011
Imperial College London
2011
Clouds of two to about fifty simultaneously stored, laser-cooled ${\mathrm{Mg}}^{+}$ ions in a Paul trap were observed phases, which are clearly distinguishable by their excitation spectra. Transitions between these phases can be induced either variation the power laser radiation used cool or change size radio-frequency voltage applied trap. "crystalline" phase and "gaseous" repeatedly appropriate parameters. The transitions them have also been recorded photon-counting image system.
We present a new experimental value for the magnetic moment of electron bound in hydrogenlike carbon (12C5+): g(exp) = 2.001 041 596 (5). This is most precise determination an atomic g(J) factor so far. The experiment was carried out on single 12C5+ ion stored Penning trap. high accuracy made possible by spatially separating induction spin flips and analysis direction. current theoretical amounts to g(th) 591 (7). Together theory test bound-state QED contributions precision 1%.
We present recent experimental and theoretical results on the behavior of two-, three-, four-ion crystals close to Mathieu instability. In particular, we show that are stable until instability is reached, i.e., for parameter space investigated, there no ``melting'' crystals. Laser rf heating studied in detail. A simple model chaotic as well a classification ion dynamics into four characteristic regimes presented.
We present an experimental value for the g factor of electron bound in hydrogenlike oxygen, which is found to be g(expt)=2.000 047 025 4 (15)(44). The experiment was performed on a single 16O7+ ion stored Penning trap. For first time, expected line shape g-factor resonance calculated essential minimizing systematic uncertainties. measurement agrees within 1.1 sigma with predicted theoretical g(theory)=2.000 020 2 (6). It represents stringent test bound-state quantum electrodynamics 0.25%...
A new independent value for the electron's mass in units of atomic unit is presented, m(e) = 0.000 548 579 909 2(4) u. The obtained from our recent measurement g factor electron (12)C(5+) combination with most quantum electrodynamical (QED) predictions. In QED corrections, terms order alpha(2) were included by a perturbation expansion Zalpha. Our total precision three times better than that accepted mass.
Using a new bunched-beam technique in the GSI heavy-ion experimental storage ring (ESR), we performed precision laser spectroscopy on relativistic heavy ions hitherto inaccessible infrared optical region. We determined wavelength of $M1$ transition between $F\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1$ $(\ensuremath{\tau}\ensuremath{\approx}50\mathrm{ms})$ and $F\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0$ hyperfine states $1s$ ground state hydrogenlike...
We determined the experimental value of g factor electron bound in hydrogenlike ²⁸Si¹³⁺ by using a single ion confined cylindrical Penning trap. From ratio ion's cyclotron frequency and induced spin flip frequency, we obtain = 1.995 348 958 7(5)(3)(8). It is excellent agreement with state-of-the-art theoretical 0(17), which includes QED contributions up to two-loop level order (Zα)² (Zα)⁴ represents stringent test bound-state quantum electrodynamics calculations.
The CPT theorem (the assumption that physical laws are invariant under simultaneous charge conjugation, parity transformation and time reversal) is central to the standard model of particle physics; here charge-to-mass ratio antiproton compared proton, with a precision 69 parts per trillion, result supports at atto-electronvolt scale. theorem, reversal, physics. Consequently, tests window onto physics beyond model. Here, Stefan Ulmer et al. test by measuring whether particles antiparticles,...
The magnetic moment of the antiproton is measured at parts-per-billion level, improving on previous measurements by a factor about 350. Comparing fundamental properties normal-matter particles with their antimatter counterparts tests charge–parity–time (CPT) invariance, which an important part standard model particle physics. Many have been to level uncertainty, but has not. Christian Smorra and colleagues now done so, report that it −2.7928473441 ± 0.0000000042 in units nuclear magneton....
Nailing down the proton magnetic moment Fundamental physical laws are believed to remain same if subjected three simultaneous transformations: flipping sign of electric charge, taking a mirror image, and running time backward. To test this parity, time-reversal (CPT) symmetry, it is desirable know fundamental properties particles such as high precision. Schneider et al. used double ion trap determine single trapped precision 0.3 parts per billion. Comparatively precise measurements quantity...
We report on the precise measurement of atomic mass a single proton with purpose-built Penning-trap system. With precision 32 parts per trillion our result not only improves current CODATA literature value by factor 3, but also disagrees it at level about 3 standard deviations.
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.
Using a phase-detection method to determine the cyclotron frequency of single trapped ion in Penning trap allowed us perform measurement $g$ factor bound electron hydrogenlike ${}^{28}$Si${}^{13+}$ with statistical uncertainty $4\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}11}$. Furthermore, we reevaluated image-charge shift as main source uncertainty. Our result challenges bound-state quantum-electrodynamical calculations by probing two-loop contributions order...
The $g$ factor of lithiumlike silicon $^{28}\mathrm{Si}^{11+}$ has been measured in a triple-Penning trap with relative uncertainty $1.1\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}9}$ to be ${g}_{\mathrm{exp}}=2.000\text{ }889\text{ }9(21)$. theoretical prediction for this value was calculated ${g}_{\mathrm{th}}=2.000\text{ }909(51)$ improving the accuracy $2.5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}8}$ due first rigorous evaluation two-photon exchange correction. is...
Abstract The magnetic moment μ of a bound electron, generally expressed by the g -factor =− B s ħ −1 with Bohr magneton and electron’s spin, can be calculated bound-state quantum electrodynamics (BS-QED) to very high precision. recent ultra-precise experiment on hydrogen-like silicon determined this value eleven significant digits, thus allowed rigorously probe validity BS-QED. Yet, investigation one most interesting contribution -factor, relativistic interaction between electron nucleus, is...
Radio-frequency induced spin transitions of one individual proton are observed. The quantum jumps detected via the continuous Stern-Gerlach effect, which is used in an experiment with a single stored cryogenic Penning trap. This important milestone towards direct high-precision measurement magnetic moment and new test matter-antimatter symmetry baryon sector.
We constrain the coupling between axionlike particles (ALPs) and photons, measured with superconducting resonant detection circuit of a cryogenic Penning trap. By searching noise spectrum our fixed-frequency for peaks caused by dark matter ALPs converting into photons in strong magnetic field Penning-trap magnet, we are able to masses around $2.7906-2.7914\,\textrm{neV/c}^2$ $g_{a\gamma}< 1 \times 10^{-11}\,\textrm{GeV}^{-1}$. This is more than one order magnitude lower best laboratory...
We report on the first observation of continuous Stern-Gerlach effect an electron bound in atomic ion. The measurement was performed a single hydrogenlike ion ( 12C5+) Penning trap. measured g factor electron, = 2.001 042(2), is excellent agreement with theoretical value, confirming relativistic correction at level 0.1%. This proves possibility g-factor determinations ions to high precision by using effect. result demonstrates feasibility conducting experiments heavy highly charged test...