相关论文: $\tau$ magnetic moment in a $\gamma \gamma$ collid…
We present a comprehensive investigation into the anomalous magnetic dipole moment ($a_\tau$) and electric dipole moment ($d_\tau$) of the $\tau$ lepton using the $\gamma\gamma \to \tau^+\tau^-$ process at future lepton colliders, with the…
We show that transverse and normal single-$tau$ polarization of $tau$ pairs produced at $e^+$ $e^-$ unpolarized collisions, at the $Z$ peak, are sensitive to weak (magnetic and electric) dipole moments of the $tau$. We also show how these…
We study the possibility that the magnetic dipole moment of light charged vector mesons could be measured from their effects in \tau^- --> V^-\nu_{\tau}\gamma decays. We conclude that the energy spectrum and angular distribution of photons…
We calculate the squared matrix element for the process e+ e- --> tau+ tau- gamma allowing for anomalous magnetic and electric dipole moments at the tau tau gamma vertex. No interferences are neglected and no approximations of light fermion…
Using the effective Lagrangian formalism, the anomalous magnetic and electric dipole moments of the tau-lepton in the $\mu^{+}\mu^{-} \rightarrow \mu^{+}\gamma^{*} \gamma^{*} \mu^{-}\rightarrow \mu^{+}\tau \bar{\tau}\mu^{-}$ process at the…
We discuss new-physics searches and symmetry tests with dipole moments, emphasizing the role of polarization observables. As a primary benchmark, we consider polarized photon fusion in the $e^+ e^-$ environment of the Super Tau-Charm…
Certain CP-odd momentum correlations in the production and subsequent decay of $\tau$ pairs in $e^+ e^-$ collisions are enhanced significantly when the $e^+$ and $e^-$ beams are longitudinally polarized. These may be used to probe the real…
The tau anomalous magnetic moment (a_tau) and electric dipole moment (d_tau) have not yet been observed. The present bounds on their values are of order 10^-2 and 10^-17 e*cm, respectively. We propose to measure a_tau with a precision of…
The anomalous magnetic ($\tilde{a}_\tau$) and electric dipole ($\tilde{d}_\tau$) moment of tau lepton described in $\tau\bar{\tau}\gamma$ vertices are studied via $\mu^{+}\mu^{-} \rightarrow \tau^+\bar{\tau}^-$ process at the Muon colliders…
The possible anomalous New Physics contributions to magnetic and electric dipole moments of the $\tau$ lepton have brought renewed interest in studying $\tau$-pair production at energies of the LHC and future colliders. We discuss effects…
The large number of $\tau$ leptons available at the Belle II experiment makes it possible to study their properties and the extent of their compositeness. Our strategy relies on three observables defined in terms of elements of the…
We present methods to measure the beam polarizations and the luminosity of $\gamma \gamma$ colliders at TeV energy scale. The beam polarizations of a $\gamma \gamma$ collider can easily be monitored by comparing the numbers of events of the…
The anomalous magnetic moment of the tau lepton $a_\tau = (g_\tau -2)/2$ strikingly evades measurement, but is highly sensitive to new physics such as compositeness or supersymmetry. We propose using ultraperipheral heavy ion collisions at…
Exact stationary solutions of the wave equation are obtained to describe the interaction between magnetic moment of elementary particle and circularly polarized photons. The obtained solutions substantially modify the conventional model of…
The anomalous magnetic (MDM) and electric (EDM) dipole moments of the $\tau$ lepton serve as crucial indicators of new physics beyond the Standard Model. Leveraging azimuthal angular asymmetry as a novel tool in ultraperipheral collisions…
A novel method for the direct measurement of the elusive magnetic and electric dipole moments of the tau lepton is presented. The experimental approach relies on the production of tau+ leptons from Ds+ -> tau+ nu_tau decays, originated in…
We have investigated the electromagnetic moments of the tau lepton in $e^{+}e^{-} \rightarrow e^{+}\gamma^{*} \gamma^{*} e^{-}\rightarrow e^{+}\tau \bar{\tau}e^{-}$ process at the CLIC. We have obtained 95% confidence level bounds on the…
The electric and magnetic dipole moments of the electron and of the muon provide stringent tests of the Standard Model and sensitive probes of new physics. By contrast, the corresponding dipole moments of the $\tau$ lepton remain weakly…
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…
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)=…