相关论文: Tau $g-2$ at $e^-e^+$ colliders with momentum depe…
The $4.2\sigma$ discrepancy in the $(g-2)$ of the muon provides a hint that may indicate that physics beyond the standard model is at play. A multi-TeV scale muon collider provides a natural testing ground for this physics. In this paper,…
We investigate the possibility of explanation for the muon anomalous magnetic moment $g_\mu-2$ in a left-right model with an inverse seesaw mechanism. We emphasize that the observed deviation from the Standard Model predictions can be…
The anomalous magnetic moment of the muon has been measured to 0.5 ppm in a series of precision experiments at the Brookhaven Alternating Gradient Synchrotron. The individual results for each sign: a(mu+)= 11 659 204(7)(5) E-10 and a(mu-) =…
We perform a detailed study of the process $e^+e^-\to \mu^+\mu^-\nu_l\bar\nu_l$ including all contributions. The contributions other than from real gauge boson production leads to a rich phenomenology. We explore the use of the process as a…
The anomalous magnetic moment of the tau lepton, $a_{\tau}$, represents a fundamental test of the Standard Model (SM) and a high-sensitivity probe for New Physics in the third generation of leptons. Due to the tau's extremely short…
We study the potential of a future $e^+e^-$ collider for the search of anomalous gamma t t bar and Z t t bar couplings, assuming that CP-invariance holds. This is done in a model-independent way, considering that all six possible couplings…
The feasibility of observing ditauonium, the bound state of two tau leptons, at $e^+e^-$ colliders (BES III at $\sqrt{s} = 3.78$ GeV, Belle II at $\sqrt{s} = 10.6$ GeV, a future super tau-charm factory (STCF) at $\sqrt{s} \approx…
We calculate the prediction for the anomalous weak-magnetic form factor of the tau lepton at $q^2=M_Z^2$ within the Standard Model. With all particles on-shell, this is a electroweak gauge invariant quantity. Its value is $a_\tau^w (M_Z^2)=…
Model independent constraints on the mass of an extra neutral gauge boson and its couplings to charged leptons are given for the $e^-e^-$ option of a future linear collider. Analytic exclusion limits are derived in the Born approximation.…
We study the experimental constraints from electron and muon $g-2$ factors on the Higgs masses and Yukawa couplings in the $T'$ model, and thereby show that the discrepancy between the standard model prediction and experimental value of…
This White Paper briefly reviews the present status of the muon (g-2) experiment and the physics motivation for a new effort. The present comparison between experiment and theory indicates a tantalizing $3.4 \sigma$ deviation. An…
Measuring the muon anomalous magnetic moment g-2 and the rare decays of light pseudoscalar mesons into lepton pair P \to l+l- serve as important test of the standard model. To reduce the theoretical uncertainty in the standard model…
The situation of the experimental data used in the dispersive evaluation of the hadronic vacuum polarization contribution to the anomalous magnetic moment of the muon is assessed in view of two recent measurements: $e^+e^- \to \pi^+\pi^-$…
We calculate (g-2)/2 of the muon, by improving the determination of the hadronic vacuum polarisation contribution, a_mu^{had,LO}, and its uncertainties. The different e+e- data sets for each exclusive (and the inclusive) channel are…
In this paper, we present detailed studies on the feasibility at $pp$, $e^-p$ and $e^+e^-$ colliders for model-independent sensitivity estimates on the total cross-section and on the anomalous $\tau^+\tau^-\gamma$ interaction through the…
A fermion can be chiral or vectorlike with respect to a given symmetry, depending on its coupling to the corresponding gauge boson. Vectorlike fermions have a distinct property that their left-handed and right-handed components behave in…
We consider a type I or type X two Higgs doublets model with a modified lepton sector. The generalized lepton sector is also flavor conserving but with the new Yukawa couplings completely decoupled from lepton mass proportionality. The…
A search is made for charged Higgs bosons predicted by Two-Higgs-Doublet extensions of the Standard Model (2HDM) using electron-positron collision data collected by the OPAL experiment at sqrt(s)=189-209 GeV, corresponding to an integrated…
We study the muon pair production $ e^+ e^- \to \mu^+ \mu^-$ in the framework of the non-minimal noncommutative(NC) standard model to the second order of the NC parameter $\Theta_{\mu\nu}$. The $\mathcal{O}(\Theta^2)$ momentum dependent NC…
We investigate the prospects of the search for a nonzero $\tau$ EDM form factor $d_\tau(s)$ in $\tau$ pair production by $e^+ e^-$ collisions at BEPC-II collider energies. We compute the expectation values and covariances of simple and…