Related papers: New Model-Independent Limit on Muon Substructure
The most recent high-precision determination of the hadronic leading order contribution to the muon magnetic dipole moment within the Standard Model of particle physics has revealed a five standard deviation discrepancy with the previous…
We explore the possibility of the existence of excited leptons in the light of recent data on muon $g - 2$ from BNL. We have been able to put stringent bounds on the relevant parameter space.
A new scalar particle with generic couplings to the standard-model particles is a possible source for the lepton anomalous magnetic moment and the violation of the weak equivalence principle. Here, one-loop contributions to the lepton…
The effect of the recently observed 2.6 sigma deviation of the muon anomalous magnetic moment (a_mu = (g_mu -2)/2) from its Standard Model prediction is examined within the framework of supergravity models with grand unification and R…
I present a fairly detailed discussion of various contributions to the anomalous magnetic moment of the muon a_mu. I try to give an unbiased evaluation of the validity of the SM prediction for this quantity and to point out some delicate…
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.…
The E821 experiment at Brookhaven National Laboratory is designed to measure the muon magnetic anomaly, a_mu, to an ultimate precision of 0.4 parts per million (ppm). Because theory can predict a_mu to 0.6 ppm, and ongoing efforts aim to…
Bounds on the anamolous magnetic moment of the tau neutrino are calculated through the reaction (e+e-)-->nunu(bar)gamma at the neutral boson pole and in the framework of an extended standard model, a left-right symmetric model and a…
A new upper limit for the probability of spontaneous muonium to antimuonium conversion was established at ${\rm P_{M\bar{M}}} \leq 8.2 \cdot 10^{-11}$ (90%C.L.) in 0.1~T magnetic field, which implies consequences for speculative extensions…
We investigate the use of effective Lagrangians to describe the effects on high-precision observables of physics beyond the Standard Model. Using the anomalous magnetic moment of the muon as an example, we detail the use of effective…
The ideas and formulas presented in the article will help to bring together the theoretical predictions for the anomalous magnetic moment of muon and the results of the "Muon g-2" experiment. In doing so, we are discussing the new effect…
We amalgamate the many experimental limits on the $ab\anti b$ coupling of a light CP-odd Higgs boson, $a$, including model-dependence coming from the ratio of the $at\anti t$ to the $a b\anti b$ coupling. We then employ these limits to…
The anomalous magnetic moment of the negative muon has been measured to a precision of 0.7 parts per million (ppm) at the Brookhaven Alternating Gradient Synchrotron. This result is based on data collected in 2001, and is over an order of…
The muon magnetic anomaly may contain contributions from physics beyond the standard model. At the Brookhaven National Laboratory (BNL) a precision experiment aims for a measurement of the muon magnetic anomaly $a_{\mu}$ to 0.35 ppm, where…
We present a new, completely revised calculation of the muon anomalous magnetic moment, $a_\mu=(g_{\mu}-2)/2$, comparing it with the more recent experimental determination of this quantity; this furnishes an important test of theories of…
The width for the mu decay is calculated in the V-A theory leaving open the possibility of non zero neutrino masses. It is shown that not only the agreement with the experimental data is kept, but the smallness of the experimental error…
A model with $L_{\mu} -L_{\tau}$ gauge symmetry is the least constrained model as a resolution to the disagreement of the muon anomalous magnetic moment between the theoretical predictions and the experimental results. In this paper, we…
Motivated by speculations about infrared deviations from the standard behavior of local quantum field theories, we explore the possibility that such effects might show up as an anomalous running of coupling constants. The most sensitive…
It is shown that it follows from our model of the electron that its magnetic moment has an anomalous part if the magnetic field energy is taken into account. That means that the magnetic moment of our model of the electron is 1.0000565…
Theoretical calculations of the hadronic contribution to the muon anomalous magnetic moment utilize experimental data from e+e- annhilation and tau decay. The data provide input to a dispersion relation. I contend that it is not possible to…