A5070668664- Atomic and Molecular Physics
- Muon and positron interactions and applications
- Advanced Chemical Physics Studies
- Radioactive Decay and Measurement Techniques
- Scientific Measurement and Uncertainty Evaluation
- Cold Atom Physics and Bose-Einstein Condensates
- Particle physics theoretical and experimental studies
- Nuclear physics research studies
- Advanced Frequency and Time Standards
- Particle accelerators and beam dynamics
- Quantum and Classical Electrodynamics
- Atomic and Subatomic Physics Research
- Quantum Chromodynamics and Particle Interactions
- Dark Matter and Cosmic Phenomena
- Quantum Mechanics and Applications
- High-Energy Particle Collisions Research
- Scientific Research and Discoveries
- Quantum, superfluid, helium dynamics
- Spectroscopy and Laser Applications
- Chemical Thermodynamics and Molecular Structure
- Cosmology and Gravitation Theories
- Quantum optics and atomic interactions
- Experimental and Theoretical Physics Studies
- History and advancements in chemistry
- Molecular Spectroscopy and Structure
Max Planck Institute of Quantum Optics
2012-2023
Ludwig-Maximilians-Universität München
2017-2023
Pulkovo Observatory
2011-2021
Technical University of Munich
2019
D.I. Mendeleyev All-Russian Institute for Metrology
2002-2018
University of Alberta
2017
Max Planck Society
2005-2015
All-Russian research Institute of metrological service
2000-2009
All-Russian Scientific Research Institute of Butter and Cheese Making
1996-2008
State Research Center of the Russian Federation
2008
Sufficient progress towards redefining the International System of Units (SI) in terms exact values fundamental constants has been achieved. Exact Planck constant h, elementary charge e, Boltzmann k, and Avogadro NA from CODATA 2017 Special Adjustment Fundamental Constants are presented here. These recommended to 26th General Conference on Weights Measures form foundation revised SI.
The comparison of different atomic transition frequencies over time can be used to determine the present value temporal derivative fine structure constant $\ensuremath{\alpha}$ in a model-independent way without assumptions on constancy or variability other parameters, allowing tests consequences unification theories. We have measured an optical frequency at 688 THz $^{171}\mathrm{Y}\mathrm{b}^{+}$ with cesium clock 2 times separated by 2.8 yr and find for fractional variation ratio...
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.
As an unstable light pure leptonic system, positronium is a very specific probe atom to test bound state QED. In contrast ordinary QED for free leptons, the theory not so well understood and approaches deserve highly accurate tests. We present brief overview of precision studies paying special attention uncertainties as comparison experiment. also consider in detail advantages disadvantages tests compared other experiments.
We consider different options for the search possible variations of fundamental constants. give a brief overview results obtained with several methods. discuss their advantages and disadvantages respect to simultaneous all constants in both time space range 10 8 10 years. also suggest few possibilities laboratory search. Particularly, we propose some experiments hyperfine structure hydrogen, deuterium, ytterbium171 atoms small magnetic moment. Other suggestions are measurements fine...
Constraint on spin-dependent and spin-independent Yukawa potential at atomic scale is developed. That covers constraints a coupling constant of an additional photon γ* pseudovector boson. The mass range considered from 1 eV/c2 to MeV/c2. strongest constraint α' the level few parts in 10913) (for γ*) below one part 10(16) pseudovector) corresponding keV/c2. are derived low-energy tests quantum electrodynamics based spectroscopic data light hydrogenlike atoms experiments with magnetic moments...
The recent measurement of the Lamb shift in muonic hydrogen allows for most precise extraction charge radius proton which is currently conflict with other determinations based on $e\ensuremath{-}p$ scattering and spectroscopy. This discrepancy could be result some new muon-specific force O(1--100) MeV carrier---in this paper we concentrate vector mediators. Such an explanation faces challenges from constraints imposed by $g\ensuremath{-}2$ muon electron as well precision spectroscopy atoms....
The determination of the electron mass from Penning-trap measurements with $^{12}$C$^{5+}$ ions and theoretical results for bound-electron $g$ factor is described in detail. Some recently calculated contributions slightly shift extracted value. Prospects a further improvement are discussed both experimental point view. Measurements $^4$He$^+$ will enable consistency check value, future an $^4$He nuclear fine-structure constant.
Constraints on a spin-independent interaction by exchange of neutral light boson are derived from precision data the electron anomalous magnetic moment and atomic spectroscopy hydrogen deuterium atoms. The mass range $1 $eV$/c^2$ to $Mev$/c^2$ is studied effective coupling constant $\alpha^\prime$ allowed below level $10^{-11} - 10^{-13}$ depending value mass. corresponds Yukawa radius 0.0002 nm 20 nm, which covers distances far above Bohr atom.
There has been for a while large discrepancy between the values of proton charge radius measured by Lamb shift in muonic hydrogen and other methods. It already clear that theory is reliable at level this an error there cannot be reason contradiction. Still status uncertainty muonic-hydrogen experiment (which two orders magnitude below level) requires additional clarification. Here, we revisit 2p − 2s hydrogen. We summarize all theoretical contributions order α5m, including pure quantum...
Abstract The energy levels of hydrogen-like atoms and ions are accurately described by bound-state quantum electrodynamics (QED). $$\hbox {He}^{+}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mtext>He</mml:mtext> <mml:mo>+</mml:mo> </mml:msup> </mml:math> have a doubly charged nucleus, which enhances the higher-order QED contributions makes them interesting for precise tests QED. Systematic effects that currently dominate uncertainty in hydrogen spectroscopy,...
We have applied an optical method to the measurement of 2S hyperfine interval in atomic hydrogen. The has been measured by means two-photon spectroscopy 1S-2S transition on a hydrogen beam shielded from external magnetic fields. value is equal 177 556 860(16) Hz and represents most precise this date. theoretical evaluation specific combination 1S intervals D21 fair agreement (within 1.4 sigma) with for deduced our measurement.
The contribution of the light-by-light diagram to g factor electron and muon bound in Coulomb field is obtained. For a ground state, our results are good agreement with other authors obtained numerically for large Z. relatively small Z have essentially higher accuracy as compared previous ones. muonic atoms, first time high whole region
An optical measurement of the 2S hyperfine interval in atomic hydrogen using two-photon spectroscopy 1S-2S transition gives a value 177 556 834.3(6.7) Hz. The uncertainty is 2.4 times smaller than achieved by our group 2003 and more 4 for any independent radio-frequency measurement. specific combination 1S intervals predicted QED theory 8fHFS(2S)-fHFS(1S)=48 953(3) Hz good agreement with 48 923(54) obtained from this experiment.
Contributions to the energy levels in light muonic atoms and, particular, Lamb shift fall into a few well-distinguished classes. The related diagrams are calculated using different approaches. In there is specific kind of non-relativistic contributions. Here we consider such corrections order $\alpha^5m_\mu$. These contributions due free vacuum polarization loops as well various effects light-by-light scattering. closed loop an electronic one, which allows consideration muon. Both kinds have...
The relativistic recoil contributions to the Uehling corrections are revisited. We consider a controversy in recent calculations based on different approaches including Breit-type and Grotch-type calculations. have found that of those authors were fact done gauges some retardation two-photon-exchange effects missed. evaluated such obtained consistent result from approaches. present correct expression for approach which produces gauge-invariant result. also finite-nuclear-size correction...