Related papers: Measured Lepton Magnetic Moments
Standard Model contributions to the electron, muon, and tau lepton anomalous magnetic moments, a_l=(g_l-2)/2, are reviewed and updated. The fine structure constant is obtained from the electron g_e-2 and used to refine the QED contribution…
A review of the experimental and theoretical determinations of the anomalous magnetic moment of the muon is given. The anomaly is defined by a=(g-2)/2, where the Land\'e g-factor is the proportionality constant that relates the spin to the…
Precision experiments with muons are sensitive to Planck-scale CPT and Lorentz violation that is undetectable in other tests. Existing data on the muonium ground-state hyperfine structure and on the muon anomalous magnetic moment could be…
The "precision" frontier, which is closely related to the "intensity" frontier, provides a complementary path to the discovery of physics beyond the Standard Model. Several examples of discoveries that would change our view of the physical…
New sources of CP violation beyond the Standard Model of particle physics could be revealed in the laboratory by measuring a non-zero electric dipole moment (EDM) of a spin 1/2 particle such as the neutron. Despite the great sensitivity…
The calculations entering the prediction of the standard model value for the anomalous magnetic moment of the muon $a_\mu$ are reviewed, and compared to the very accurate experimental measurement. The situation for the electron is discussed…
We review the role of the anomalous magnetic moment of the muon a_\mu as a powerful probe of physics beyond the Standard Model (BSM), taking advantage of the final result of the Fermilab g-2 experiment and the recently updated Standard…
The energy levels of the muonium ($\mu^+ e^-$) atom, which consists of two ''point-like'' leptonic particles, can be calculated to very high accuracy in the framework of bound state Quantum Electrodynamics (QED), since there are no…
The "proton size puzzle" and the "muon anomalous moment problem" are incomplete descriptions of significant discrepancies of Standard Model calculations with experiments. What is particularly new is that the experiments and theory confront…
The muon anomalous magnetic moment measurement, when compared with theory, can be used to test many extensions to the standard model. The most recent measurement made by the Brookhaven E821 Collaboration reduces the uncertainty on the world…
We perform a model-independent analysis of the magnetic and electric dipole moments of the muon and electron. We give expressions for the dipole moments in terms of operator coefficients of the low-energy effective field theory (LEFT) and…
Quantities like the fine structure constant at the pole of the Z boson and the anomalous magnetic moment of the muon are of profound importance for testing the Standard Model of elementary particle physics. Because these quantities are…
We report a measurement of the positive muon lifetime to a precision of 1.0 parts per million (ppm); it is the most precise particle lifetime ever measured. The experiment used a time-structured, low-energy muon beam and a segmented plastic…
Electromagnetic moments of particles carry important information on their internal structure, as well as on the structure of the effective Lagrangian describing their underlying field theory. One of the cleanest observable of such kind is…
Precise measurements of the lepton properties provide stringent tests of the Standard Model structure and accurate determinations of its parameters. We overview the present status of a few selected topics: lepton universality, QCD tests and…
An Effective Field Theory (EFT) analysis of the magnetic moment of the muon is discussed. The expression for the dipole moment is given in terms of operator coefficients of the low-energy effective field theory (LEFT) and the Standard Model…
We calculate chirally enhanced corrections to the muon's electric and magnetic dipole moments in two-Higgs-doublet models extended by vector-like leptons, and we explore a sharp correlation between $h \rightarrow \mu^+ \mu^-$ and the muon's…
We investigate contributions to the anomalous magnetic moments of charged leptons in the neutrino-extended Standard Model Effective Field Theory ($\nu$SMEFT). We discuss how $\nu$SMEFT operators can contribute to a lepton's magnetic moment…
The existence of magnetic moments of neutrinos points to physics beyond the standard model. Given current upper limits, terrestrial measurements are difficult or completely unfeasible. However, estimates of transition moments can be…
Electric dipole moments are extremely sensitive probes of physics beyond the Standard Model. A vibrant experimental program is in place, with the goal of improving existing bounds on the electron and neutron electric dipole moments by one…