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Related papers: Tau EDM at Low Energies

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The electric dipole moment (EDM) of electron is studied in the supersymmetric $\rm A_4$ modular invariant theory of flavors with CP invariance. The CP symmetry of the lepton sector is broken by fixing the modulus $\tau$. Lepton mass…

High Energy Physics - Phenomenology · Physics 2021-11-10 Morimitsu Tanimoto , Kei Yamamoto

I present a review of current and near-future experimental investigations of CP violation. In this review, I cover limits on particle electric dipole moments (EDMs) and CP violation studies in the K and B systems. The wealth of results from…

High Energy Physics - Experiment · Physics 2010-11-05 Owen Long

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

We show that the CP-violating dipole form factors of the tau lepton can be of the order of $\alpha/\pi$ in units of the length scale set by the inverse $Z$ boson mass. We propose a few observables which are sensitive to these form factors…

High Energy Physics - Phenomenology · Physics 2016-09-06 W. Bernreuther , A. Brandenburg , P. Overmann

We derive an upper limit on the electric dipole moment (EDM) of the tau-lepton, which follows from the precision measurements of the electron EDM.

High Energy Physics - Phenomenology · Physics 2009-08-05 A. G. Grozin , I. B. Khriplovich , A. S. Rudenko

CP violating dipole moments of leptons vanish at least to three loop order and are estimated to be $({m_l\over Mev})\times 1.6\times 10^{- 40}$ e-cm in the standard model (SM), where $m_l$ is the mass of the lepton. However they can receive…

High Energy Physics - Phenomenology · Physics 2016-09-01 Uma Mahanta

We have searched for a T/CP violation signature arising from an electric dipole form factor (d_tau) of the tau lepton in the e+e- -> tau+tau- reaction. Using an optimal observable method for 29.5 fb^{-1} of data collected with the Belle…

High Energy Physics - Experiment · Physics 2008-11-26 K. Inami , Belle collaboration

In this work, we study the possible unparticle signatures through tau pair production e+e- -> tau+tau- process at the low energy particle factories. We take into account lepton flavor conserving (s-channel) and violating (t-channel)…

High Energy Physics - Phenomenology · Physics 2009-06-16 O. Cakir , K. O. Ozansoy

New sources of CP violation, beyond the known sources in the standard model (SM), are required to explain the baryon asymmetry of the universe. Measurement of a non-zero permanent electric dipole moment (EDM) for fundamental particles, such…

Nuclear Experiment · Physics 2021-05-05 Prajwal Mohanmurthy , Jeff A. Winger

Tau-pair production in the process e+e- -> e+e-tau+tau- was studied using data collected by the DELPHI experiment at LEP2 during the years 1997 - 2000. The corresponding integrated luminosity is 650 pb^{-1}. The values of the cross-section…

High Energy Physics - Experiment · Physics 2008-11-26 The DELPHI Collaboration , J. Abdallah

We review world-average measurements of the tau lepton electroweak couplings, in both decay (including Michel parameters) and in production ($Z^0\to \tau^+\tau^-$ and $W^-\to\tau^-\nubar_\tau$). We review the searches for anomalous weak and…

High Energy Physics - Experiment · Physics 2007-05-23 Alan J. Weinstein

We consider the production of tau pairs by electron-positron colliding beams at the maximum cross section near the threshold. At this energy tau pairs are produced mostly in the s-wave which implies that the spin of the tau pairs are almost…

High Energy Physics - Phenomenology · Physics 2009-12-30 Yung Su Tsai

Precise measurement of the Electric Dipole Moment (EDM) and anomalous magnetic moment ($g$-2) of particles are important tests of Beyond Standard Model (BSM) physics. It is generally believed that the tau lepton couples more strongly to BSM…

High Energy Physics - Phenomenology · Physics 2020-01-08 Xin Chen , Yongcheng Wu

The proposed high-luminosity B/Flavor factories offer new opportunities for the improved determination of the fundamental physical parameters of standard heavy leptons. Compared to the electron or the muon case, the magnetic properties of…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. Bernabeu , G. A. Gonzalez-Sprinberg , J. Papavassiliou , J. Vidal

We study the leptonic CP violation by employing the complete set of dimension-six pure leptonic effective operators. Connection among the observable at different energy scales can be made by the running of the renormalization group…

High Energy Physics - Phenomenology · Physics 2009-11-11 We-Fu Chang , John N. Ng

Some recent $\tau$-physics results are presented from the BaBar and Belle experiments at the SLAC and KEK B factories, which produce copious numbers of $\tau$-lepton pairs. Measurements of the tau mass and lifetime allow to test lepton…

High Energy Physics - Experiment · Physics 2009-11-11 G. D. Lafferty

The capability of current and future measurements at low and high energy $e^+e^-$ colliders to probe for the existence of anomalous, CP conserving, $\tau \nu W$ dipole moment-type couplings is examined. At present, constraints on the…

High Energy Physics - Phenomenology · Physics 2009-10-30 Thomas G. Rizzo

In this study, we investigate the potential of the process $pp\rightarrow p\gamma^{*} p\rightarrow p \tau \bar{\nu}_{\tau}q^{\prime} X$ at the LHC to examine the anomalous electromagnetic moments of the tau lepton. We obtain $95\%$…

High Energy Physics - Phenomenology · Physics 2018-07-24 M. Köksal , S. C. İnan , A. A. Billur , M. K. Bahar , Y. Özgüven

This study investigates the intrinsic electric dipole moment (EDM) of the $\tau$ lepton, which is an important quantity in the search for physics beyond the Standard Model (BSM). In preparation for future measurements at the Super Tau-Charm…

High Energy Physics - Experiment · Physics 2025-09-09 Xulei Sun , Yongcheng Wu , Xiaorong Zhou

We reconsider the issue of the search for a nonzero electric dipole form factor (EDM) $d_\tau(s)$ using optimal observables in $\tau^+\tau^-$ production by $e^+ e^-$ collisions in the center-of-mass energy range from the $\tau$-pair…

High Energy Physics - Phenomenology · Physics 2021-05-19 Werner Bernreuther , Long Chen , Otto Nachtmann