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Related papers: Limits on Anomalous Top Couplings from Z Pole Phys…

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In this thesis we investigated, at partonic level and leading order, the LHC potencial operating with $\sqrt{s}=14$ TeV and integrated luminosity of $L=100\;{fb}^{-1}$ to probe "pure" (without triple vertex contributions) anomalous…

High Energy Physics - Phenomenology · Physics 2013-03-05 Patricia Rebello Teles

We propose to probe the electroweak symmetry breaking sector by measuring the effective couplings of the top quark to gauge bosons. Using precision LEP data, we constrain the non--universal couplings of t-t-Z and t-b-W, parameterized by…

High Energy Physics - Phenomenology · Physics 2010-11-01 Ehab Malkawi , C. --P Yuan

We review the effects of new effective interactions on the Higgs boson phenomenology. New physics in the electroweak bosonic sector is expected to induce additional interactions between the Higgs doublet field and the electroweak gauge…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. C. Gonzalez-Garcia

We compute the real and imaginary parts of the one-loop electroweak contributions to the left and right tensorial anomalous couplings of the $tbW$ vertex in the Standard Model (SM). For both tensorial couplings we find that the real part of…

High Energy Physics - Phenomenology · Physics 2015-05-28 Gabriel A. González-Sprinberg , Roberto Martínez , Jorge Vidal

We derive bounds on Higgs and gauge--boson anomalous interactions using the LEP2 data on the production of three photons and photon pairs in association with hadrons. In the framework of $SU(2)_L \otimes U(1)_Y$ effective Lagrangians, we…

High Energy Physics - Phenomenology · Physics 2009-10-31 O. J. P. Eboli , M. C. Gonzalez-Garcia , S. M. Lietti , S. F. Novaes

Anomalous moments of the top quark arises from one loop corrections to the vertices $\bar t t g$ and $\bar t t \gamma$. We study these anomalous couplings in different frameworks: effective theories, Standard Model and 2HDM. We use…

High Energy Physics - Phenomenology · Physics 2014-11-17 R. Martinez , N. Poveda , J. -Alexis Rodriguez

We reconsider the prospects for observing a dimension-6, CP-violating operator involving $W^+W^-Z$ at the LHC. Firstly, we correct a number of earlier calculations of the loop contribution to the neutron electric dipole moment of a…

High Energy Physics - Phenomenology · Physics 2015-04-08 Ben Gripaios , Dave Sutherland

In this study, we explore the effects of $\mathcal CP$-violating anomalous interactions of the top-quark through the semileptonic decay modes of the top-quark arising due to pair-production of $t\bar{t}$ at the Large Hardon Collider.…

High Energy Physics - Phenomenology · Physics 2022-11-10 Apurba Tiwari , Sudhir Kumar Gupta

We establish constraints on a general four-fermion contact interaction from precise measurements of electroweak parameters. We compute the one-loop contribution for the leptonic $Z$ width, anomalous magnetic, weak-magnetic, electric and…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. C. Gonzalez-Garcia , A. Gusso , S. F. Novaes

We consider the observable effects of CP-violating anomalous $ZZh$ interaction arising from gauge invariant dimension-6 operators at the Large Hadron Collider (LHC), with the purpose of distinguishing them from not only the standard model…

High Energy Physics - Phenomenology · Physics 2016-07-05 Siddharth Dwivedi , Dilip Kumar Ghosh , Biswarup Mukhopadhyaya , Ambresh Shivaji

We calculate the top quark loop corrections to the Zbb vertex in the chiral lagrangian of the dynamical electroweak symmetry breaking theory. We use the effective lagrangian based on coset space SU(2) X U(1) / U(1) with the gauge…

High Energy Physics - Phenomenology · Physics 2009-10-28 X. Zhang

We study the constraints that can be placed on anomalous $\tau$-lepton couplings at the LHC. We use an effective Lagrangian description for physics beyond the standard model which contains the $\tau$-lepton anomalous magnetic moment,…

High Energy Physics - Phenomenology · Physics 2015-05-12 Alper Hayreter , German Valencia

Using the constraint on the single top production cross-section obtained at the HERA collider, $\sigma(ep \to e t X)$, we evaluate an upper limit on oupling constant of the anomalous top quark interaction with a gluon via flavor-changing…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. A. Ashimova , S. R. Slabospitsky

We studied the dimension-6 leptonic anomalous gauge couplings in the formulation of linearly realized gauge symmetry effective Lagrangian and investigated the constraints on these anomalous couplings from the existed experimental data…

High Energy Physics - Phenomenology · Physics 2015-05-28 Sheng-Zhi Zhao , Bin Zhang

The absence of a light Higgs boson causes vector boson couplings to become strong at 1 TeV. A general framework for a systematic and consistent treatment is provided by effective theories of electroweak symmetry breaking. Already in…

High Energy Physics - Phenomenology · Physics 2009-08-21 Erik Schmidt , Michael Beyer , Henning Schroeder

We listed all possible dimension-six CP-violating $SU_c(3)\times SU_L(2)\times U_Y(1)$ invariant operators involving the third-family quarks, which can be generated by new physics at a higher energy scale. The expressions of these operators…

High Energy Physics - Phenomenology · Physics 2014-11-17 Jin Min Yang , Bing-Lin Young

The potential of the LHC for investigation of anomalous top quark interactions with gluon ($tug,tcg$) through the production of $tW$-channel of single top quark is studied. In the Standard Model, the single top quarks in the $tW$-channel…

High Energy Physics - Phenomenology · Physics 2014-11-21 S. M. Etesami , M. Mohammadi Najafabadi

Physics from beyond the Standard Model can induce four fermion operators involving a quark, an anti-quark, a lepton and an anti-lepton. The coefficients of these operators can be constrained by various observations. We update the bounds…

High Energy Physics - Phenomenology · Physics 2010-08-03 Carpentier Michael

A complete set of dimension-6 effective contact interactions involving Higgs, gauge bosons and quarks is studied. Limits on the coefficients of these new operators are obtained from the experimental values of the $Z$ and $W$ gauge bosons…

High Energy Physics - Phenomenology · Physics 2011-01-25 Alexander Belyaev , Rogerio Rosenfeld

We obtain the constraints on scalar leptoquarks coming from radiative corrections to $Z$ physics. We perform a global fitting to the LEP data including the contributions of the most general effective Lagrangian for scalar leptoquarks, which…

High Energy Physics - Phenomenology · Physics 2008-02-03 Oscar J. P. Eboli