相关论文: Lepton anomalous magnetic moments: Theory
The relativistic and quantum theoretical explanations of the magnetic moment anomaly of the electron (or proton) show that it is a complicated function of the fine structure constant. In this work, a simple non-relativistic approach shows…
We compute the contributions to the electron and muon anomalous magnetic moment induced by heavy leptons up to four-loop order. Asymptotic expansion is applied to obtain three analytic expansion terms which show rapid convergence.
We calculate the anomalous magnetic moment for muons at one loop level arising from left right symmetric excited leptons which are excited states of known standard model leptons. Such excited states arise in compositeness theories where the…
It is shown that a minimal extension of the standard model with leptons that transform as singlets under the SU(2) symmetry of weak interactions can explain the recently reported derivation in the measured value of the anomalous magnetic…
We investigate the effects induced by excited leptons, at the one-loop level, in the anomalous magnetic and weak-magnetic form factors of the leptons. Using a general effective Lagrangian approach to describe the couplings of the excited…
The measurement of the anomalous magnetic moment of the muon provides a stringent test of the standard model and of any physics that lies beyond it. There is currently a deviation of $3.1\sigma$ between the standard model prediction for the…
We study the magnetic moment of leptons in extremely hot universe and superdense media of stars at high temperatures. Anomalous magnetic moment of charged leptons is inversely proportional to its mass, whereas, the induced dipole moment of…
In this work we consider a model including dark sector bosons interacting through tensor currents with Standard Model leptons. We show that for certain values of the interaction constant this model has the potential of providing an…
Interaction of charged leptons with photons is considered for the case when one of the lepton legs is off the mass shell. The effect due to off-mass-shell shift in the anomalous magnetic moment is computed within one-loop approximation.…
We calculate the contribution to the anomalous magnetic moment of leptons in the type-I and type-III seesaw models. We show that, even if the scale of the new physics is pushed down to the electroweak scale, this contribution is not large…
The limits on lepton radii and contact interaction scales are used to derive limits on the deviations of lepton anomalous magnetic dipole moments (g-2)/2 from the Standard Model predictions. In the case of quadratic dependence of the…
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…
The leptons are viewed as composite objects, exhibiting anomalous magnetic moments and anomalous flavor-changing transition moments. The decay $\mu \to e \gamma$ is expected to occur with a branching ratio of the same order as the present…
The electron and muon anomalous magnetic moments (AMM) are measured in experiments and studied in the Standard Model (SM) with the highest precision accessible in particle physics. The comparison of the measured quantity with the SM…
A simple physical insight into the origin of the magnetic moment anomaly of electron is presented. This approach is based on the assumption that the electromagnetic mass of the electron due to the electric field generated by electron charge…
The recent result from the E821 experiment at BNL on the anomalous magnetic moment of the muon shows a distinct discrepancy with the Standard Model predictions. We calculate the additional correction that the anomalous magnetic moment…
The $\tau$ lepton anomalous magnetic moment: $a_\tau = \frac{g_{\tau}-2}{2}$ was measured, so far, with a precision of only several percents despite its highly sensitivity to physics beyond the Standard Model such as compositeness or…
Precise measurements of magnetic and electric dipole moments are important tests of the Standard Model and beyond Standard Model physics, particularly for the electron and the muon. However, the situation presents distinctive challenges…
Extensions of the Standard Model featuring excited fermions present an interesting framework that motivates the search for exotic particles at the LHC. Additionally, these extensions offer potential explanations for the muon's anomalous…
We argue that the anomalous magnetic moment of the electron (a_e) can be used to probe new physics. We show that the present bound on new-physics contributions to a_e is 8*10^-13, but the sensitivity can be improved by about an order of…