English
Related papers

Related papers: Complex $\tau$ Electric Dipole Moment from GeV-Sca…

200 papers

Tau leptons are powerful tools to probe physics beyond the Standard Model (SM). The Belle II experiment is installed at the SuperKEKB asymmetric energy electron-positron collider and aims at collecting the world's largest sample of tau pair…

High Energy Physics - Experiment · Physics 2023-08-21 Laura Zani

A nonzero electric dipole moment of a tauon, $d_\tau$, signals CP violation and provides an important probe for new physics. We study methods to measure $d_\tau$ at low energy $e^+ e^-$ colliders through the processes $e^+e^- \to \gamma^*,…

High Energy Physics - Phenomenology · Physics 2025-03-31 Xiao-Gang He , Chia-Wei Liu , Jian-Ping Ma , Chang Yang , Zi-Yue Zou

We show that the precise determination of the Tau magnetic properties is possible in the next generation accelerators, specially at B/Flavour factories. We define spin correlation observables suitable to extract the real part of the…

High Energy Physics - Phenomenology · Physics 2009-01-30 J. Bernabeu , G. A. Gonzalez-Sprinberg , J. Vidal

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…

High Energy Physics - Phenomenology · Physics 2025-07-23 G. A. González-Sprinberg

We examine the muon's electric dipole moment $\dmu$ from a variety of theoretical perspectives. We point out that the reported deviation in the muon's g-2 can be due partially or even entirely to a new physics contribution to the muon's…

High Energy Physics - Phenomenology · Physics 2008-11-26 Jonathan L. Feng , Konstantin T. Matchev , Yael Shadmi

We propose to search for a heavy neutral lepton (HNL), that is also know as sterile neutrino, in electron colliders running with the center-of-mass energies at few GeV, including BESIII, Belle II, and the proposed Super Tau Charm Factory…

High Energy Physics - Phenomenology · Physics 2022-05-11 Yu Zhang , Mao Song , Ran Ding , Liangwen Chen

We investigate the minimal $U(1)_{L_\mu-L_\tau}$ model with extra heavy vector-like leptons or charged scalars. By studying the kinetic mixing between $U(1)_{L_\mu-L_\tau}$ gauge boson $Z^\prime$ and standard model photon, which is absent…

High Energy Physics - Phenomenology · Physics 2021-01-13 Yu Zhang , Zhuo Yu , Qiang Yang , Mao Song , Gang Li , Ran Ding

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…

High Energy Physics - Phenomenology · Physics 2021-12-15 Werner Bernreuther , Long Chen , Otto Nachtmann

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…

High Energy Physics - Phenomenology · Physics 2026-04-17 Dario Buttazzo , Gabriele Levati , Yang Ma , Fabio Maltoni , Paride Paradisi , ZeQiang Wang

Using the ARGUS detector at the e+e- storage ring DORIS II, we have searched for the real and imaginary part of the electric dipole formfactor d_tau of the tau lepton in the production of tau pairs at q^2=100 GeV^2. This is the first direct…

High Energy Physics - Experiment · Physics 2008-11-26 H. Albrecht , ARGUS Collaboration

Three new observables for Z-factory to measure the weak dipole moment of $\tau$ lepton ($d_w^\tau$) are proposed. As those observables employed at LEP-I, the new observables depend on the real and imaginary parts of $d_w^\tau$ linearly,…

High Energy Physics - Phenomenology · Physics 2015-03-17 Qing-Jun Xu , Chao-Hsi Chang

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…

High Energy Physics - Phenomenology · Physics 2015-06-12 Matteo Fael , Lorenzo Mercolli , Massimo Passera

We study the interplay of New Physics (NP) among the lepton magnetic moment, the lepton flavor violation (LFV) and the electron electric dipole moment (EDM) in light of recent data of the muon $(g-2)_\mu$. The NP is discussed in the…

High Energy Physics - Phenomenology · Physics 2024-03-15 Morimitsu Tanimoto , Kei Yamamoto

The electromagnetic and weak dipole moments of the Tau-lepton have been measured by experiments at e+e- colliders. Data samples of e+e- --> tau+tau-, e+e- --> tau+tau- gamma and e+e- --> e+e-tau+tau- events collected at centre-of-mass…

High Energy Physics - Experiment · Physics 2009-11-11 W. Lohmann

Precise measurements of the electromagnetic dipole moments of charged leptons are powerful probes of physics beyond the Standard Model of particle physics. It is essential to study avenues for optimizing the measurement strategies for the…

High Energy Physics - Phenomenology · Physics 2024-10-31 Kartik Bhide , Valerie Lang

We calculate the electric dipole moment of electron using the experimental result of muon electric dipole moment and upper limit of the BR(\mu --> e\gamma) in the framework of the general two Higgs doublet model. Our prediction is 10^{-32}…

High Energy Physics - Phenomenology · Physics 2009-11-07 E. O. Iltan

The anomalous magnetic moment of the tau lepton, a_tau = (g_tau - 2)/2, is a sensitive probe of new physics but is extremely difficult to measure precisely in contrast to electron and muon moments. The best experimental limits were set by…

High Energy Physics - Phenomenology · Physics 2025-07-16 Nazar Burmasov , Evgeny Kryshen , Paul Buehler , Roman Lavicka

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…

High Energy Physics - Phenomenology · Physics 2019-06-26 M. Köksal , A. A. Billur , A. Gutiérrez-Rodríguez , M. A. Hernández-Ruíz

Potential of the LHC to determine the electromagnetic couplings of the $\tau$ lepton is discussed via the process ${\gamma\gamma \to \tau^{+}\tau}^{-}$. Highly improved constraints of the anomalous magnetic and electric dipole moments have…

High Energy Physics - Phenomenology · Physics 2011-03-17 S. Atag , A. A. Billur

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…

High Energy Physics - Phenomenology · Physics 2024-08-30 H. Denizli , A. Senol , M. Köksal