Related papers: Mass Measurements and the Bound--Electron g Factor
The persistent $a_\mu \equiv (g-2)/2$ anomaly in the muon sector could be due to new physics visible in the electron sector through a sub-ppb measurement of the anomalous magnetic moment of the electron $a_e$. Driven by recent results on…
The precise determination of the proton radius from recent elastic scattering electron-proton data is discussed. The necessary precision on the elastic cross section to discriminate among the values coming from atomic spectroscopy is…
A rigorous QED evaluation of the two-photon exchange corrections to the g factor of lithiumlike ions is presented. The screened self-energy corrections are calculated for the intermediate-$Z$ region and its accuracy for the high-$Z$ region…
The Standard Model of particle physics assumes that the so-called fundamental constants are universal and unchanging. Absorption lines arising in molecular clouds along quasar sightlines offer a precise test for variations in the…
Echo atom interferometers have emerged as interesting alternatives to Raman interferometers for the realization of precise measurements of the gravitational acceleration $g$ and the determination of the atomic fine structure through…
In the ALPHATRAP experiment, the $g$ factor of boron-like $^{118}\mathrm{Sn}^{45+}$ has been measured with a $0.5$ parts-per-billion uncertainty. This is the first high-precision measurement of a heavy boron-like $g$ factor. The measured…
Electric dipole moments are extremely sensitive probes for additional sources of CP violation in new physics models. The multi-scale problem of relating the high-precision measurements with neutrons, atoms and molecules to fundamental…
The hyperfine structure (hfs) and the g factor of a bound electron are caused by external magnetic fields. For the hfs, the magnetic field is due to the nuclear spin. A uniform-in-space and constant-in-time magnetic field is used to probe…
Several experiments have extracted proton electromagnetic form factors from elastic cross section measurements using the Rosenbluth technique. Global analyses of these measurements indicate approximate scaling of the electric and magnetic…
Precision measurements with ultracold molecules require development of robust and sensitive techniques to produce and interrogate the molecules. With this goal, we theoretically analyze factors that affect frequency measurements between…
We study the influence of constant magnetic field combined with a field induced by the external thermal environment on the atomic decay rates. The importance of radiative corrections, including magnetic interaction, is demonstrated for…
The agreement of electroweak measurements with theory places limits on the masses of the top quark and the $W$ boson. It is shown how these limits arise and what constraints various measurements (particularly a top quark mass determination)…
Fully relativistic approach is applied to evaluation of the nuclear recoil effect on the bound-electron $g$ factor in hydrogenlike ions to first order in the electron-to-nucleus mass ratio $m/M$ and to all orders in $\alpha Z$. The…
The nature of the theory of circular Rydberg states of hydrogenlike ions allows highly-accurate predictions to be made for energy levels. In particular, uncertainties arising from the problematic nuclear size correction which beset low…
A precise determination of the W boson mass is an essential test for the Standard Model of particle physics: the comparison of experimental value and theoretical prediction allows to probe the internal consistency of the electroweak sector…
Intensive theoretical and experimental efforts over the past decade have aimed at explaining the discrepancy between data for the proton electric to magnetic form factor ratio, $G_{E}/G_{M}$, obtained separately from cross section and…
The electron Land\'e g factor ($g^{*}$) is investigated both experimentally and theoretically in a series of GaBi$_{x}$As$_{1-x}$/GaAs strained epitaxial layers, for bismuth compositions up to $x = 3.8$%. We measure $g^{*}$ via…
There are few good direct laboratory tests of boost invariance for electrons, because the experiments required often involve repeated precision measurements performed at different times of year. However, existing measurements and…
A reanalysis of unpolarized electron-proton elastic scattering data is done in terms of the electric to magnetic form factor squared ratio. This observable is in principle more robust against experimental correlations and global…
Improved values for the two- and three-loop mass-dependent QED contributions to the anomalous magnetic moments of the electron, muon, and tau lepton are presented. The Standard Model prediction for the electron (g-2) is compared with its…