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Related papers: CP Violation in radiative Z Decays

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It has been shown that CP violating electron-nucleon and nucleon-nucleon interactions can induce atomic electric dipole moments and are therefore constrained from experimental data. We show that using the experimental upper bounds on…

High Energy Physics - Phenomenology · Physics 2009-10-28 Xiao-Gang He , Bruce McKellar

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

We calculated the differential cross sections of the processes in which one of the pair created tau particles at an e^+ e^- collider decays into lepton flavor violating final states e.g. tau -> mu gamma, tau -> 3 mu, tau -> mu ee. Using the…

High Energy Physics - Phenomenology · Physics 2009-10-31 Ryuichiro Kitano , Yasuhiro Okada

We propose a method of measuring the CP-odd part of the Yukawa interaction of Higgs boson and $\tau$ leptons by observing the forward-backward asymmetry in the decay $H \to \tau^+ \, \tau^- \, \gamma$. The source of such asymmetry is the…

High Energy Physics - Phenomenology · Physics 2024-04-16 Erlend Aakvaag , Nikolai Fomin , Anna Lipniacka , Stefan Pokorski , Janusz Rosiek , Dibyakrupa Sahoo

We introduce a methodology and investigate the feasibility of measuring quantum properties of tau lepton pairs in the $H \to \tau^+ \tau^-$ decay at future lepton colliders. In particular, observation of entanglement, steerability and…

High Energy Physics - Phenomenology · Physics 2023-05-15 Mohammad Mahdi Altakach , Priyanka Lamba , Fabio Maltoni , Kentarou Mawatari , Kazuki Sakurai

High luminosity Super B/Flavor factories, near and on top of the $\Upsilon$ resonances, allow for a detailed investigation of CP-violation in $\tau$ physics. In particular, bounds on the $\tau$ electric dipole moment can be obtained from…

High Energy Physics - Phenomenology · Physics 2007-07-12 G. A. González-Sprinberg , J. Bernabéu , J. Vidal

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

We identify new room for CP violation in lepton flavor violating observables not bound by the electric dipole moment of leptons. By focusing on new physics in the muon-electron sector, we show that CP violation can make its first appearance…

High Energy Physics - Phenomenology · Physics 2024-08-05 Diego Redigolo , Michele Tammaro , Andrea Tesi

Tests of CP violation by appropriate momentum correlations in $Z\to 3$ jets and in particular in $Z\to b\bar bX$ probe CP-violating effective couplings -- that manifest themselves as form factors -- which conserve the quark chirality and…

High Energy Physics - Phenomenology · Physics 2009-10-28 W. Bernreuther , A. Brandenburg , P. Haberl , O. Nachtmann

The dimension-six CP-violating SU_L(2)\times U_Y(1) invariant operators involving the tau lepton are studied. The constraints from the available experimental data on tau dipole moments are derived. Under the current constraints, the induced…

High Energy Physics - Phenomenology · Physics 2009-10-31 Tao Huang , Jin Min Yang , Bing-Lin Young , Xinmin Zhang

The anomalous weak dipole moments of the tau lepton are measured in a data sample collected by ALEPHfrom 1990 to 1995 corresponding to an integrated luminosity of 155pb-1. Tau leptons produced in the reaction e+e- -> tau+tau- at energies…

High Energy Physics - Experiment · Physics 2012-08-27 ALEPH Collaboration

We discuss signals for CP-violation in $\mu^+ \mu^- \to \tilde \tau_i^- \tilde \tau_j^+$, where $i,j = 1,2$ label the two scalar $\tau$ mass eigenstates. We assume that these reactions can proceed through the production and decay of the…

High Energy Physics - Phenomenology · Physics 2009-10-31 Seong-Youl Choi , Manuel Drees

The origin of the matter-antimatter asymmetry in the Universe is a fundamental question of physics. Electroweak baryogenesis is a compelling scenario for explaining it but it requires beyond the Standard Model sources of the CP symmetry…

High Energy Physics - Phenomenology · Physics 2021-07-14 J. Alonso-González , L. Merlo , S. Pokorski

We examine the CP-conserving (CPC) and CP-violating (CPV) effects of a general HZZ coupling through a study of the process H -> ZZ* -> 4 leptons at the LHC. We construct asymmetries that directly probe these couplings. Further, we present…

High Energy Physics - Phenomenology · Physics 2009-04-09 Rohini M. Godbole , David J. Miller , M. Margarete Mühlleitner

If CP violation in the decays of neutral kaons is due to phases in the weak couplings of quarks, as encoded in the Cabibbo-Kobayashi-Maskawa (CKM) matrix, there are many other experimental consequences. Notable among these are CP-violating…

High Energy Physics - Phenomenology · Physics 2009-09-25 J. Rosner

It has been pointed out recently that a certain set of dimension-6 scalar $P$- and $CP$-violating light-quark-muon operators may be tested in $\eta$ and $\eta'$ decays to various final states involving $\mu^+\mu^-$ pairs, at a level not yet…

High Energy Physics - Phenomenology · Physics 2022-12-20 Maximilian Zillinger , Bastian Kubis , Pablo Sánchez-Puertas

The tau is the only known lepton that can decay hadronically. From this class of decays, high precision measurements of several quantities can be extracted: the CKM matrix element $V_{us}$, the mass of the strange quark, etc. Also, as a…

High Energy Physics - Phenomenology · Physics 2012-08-15 A. Moyotl

New CP-violating asymmetries of decay leptons in $e^+\,e^-\;\ra\;t\,\bar{t}$, arising from electric and weak dipole couplings of $t\,\bar{t}$ to $\gamma$ and $Z$, are examined in the case of unpolarized and longitudinally polarized…

High Energy Physics - Phenomenology · Physics 2010-11-01 P. Poulose , Saurabh D. Rindani

CP violation of the charged lepton sector has not been found yet. Tau is a unique charged lepton which can decay into hadrons. In this talk, we argue what kind of new physics can be studied with CP violation of tau lepton decays. We also…

High Energy Physics - Phenomenology · Physics 2009-05-13 Daiji Kimura , Kang Young Lee , Takuya Morozumi , Keita Nakagawa

On general grounds based on quantum field theory the decay amplitude for $\Sigma^0 \to \Lambda \gamma$ consists of a parity conserving magnetic and a parity violating electric dipole transition moment. Because of the subsequent…

High Energy Physics - Phenomenology · Physics 2018-12-05 Shankar Sunil Nair , Elisabetta Perotti , Stefan Leupold