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Related papers: Constraints on Non-standard Top Quark Couplings

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We derive bounds from oblique parameters on the dimension-6 operators of an effective field theory of electroweak gauge bosons and the Higgs doublet. The loop- induced contributions to the S, T, and U oblique parameters are sensitive to…

High Energy Physics - Phenomenology · Physics 2014-02-05 Chien-Yi Chen , S. Dawson , Cen Zhang

We use dijet measurements from the Large Hadron Collider to constrain ten third-generation four-quark operators in the Standard Model effective field theory. At tree level, only the five operators involving four bottom quarks are directly…

High Energy Physics - Phenomenology · Physics 2026-03-31 Maximilian Freiheit , Ulrich Haisch

We study the estimation of anomalous charged triple gauge couplings (cTGCs) parameterized in a model-independent Standard Model effective field theory (SMEFT) framework via $WW$ production followed by semi-leptonic decay at the $e^+e^-$…

High Energy Physics - Phenomenology · Physics 2025-07-31 Sahabub Jahedi , Jayita Lahiri , Amir Subba

We classify the physical operators of the most general bosonic effective gauge theory up to dimension six using on-shell methods. Based on this classification, we compute the complete one-loop anomalous dimension employing both on-shell…

High Energy Physics - Phenomenology · Physics 2026-05-29 Jason Aebischer , Luigi C. Bresciani , Nudzeim Selimovic

I review recent progress in the computation of processes involving top quarks in the framework of Standard Model Effective Theory at NLO in QCD. In particular I discuss the impact of higher-dimensional operators on top pair production in…

High Energy Physics - Phenomenology · Physics 2016-12-01 Eleni Vryonidou

We investigate the anomalous charged triple gauge boson couplings generated via $SU(2)_l\times U(1)_Y$ gauge invariant dimension-6 operators with final state four jet events in an $e^-e^+$ Collider at $\sqrt{s}=250$~GeV. We consider all the…

High Energy Physics - Phenomenology · Physics 2024-07-02 Amir Subba , Ritesh K. Singh

We compute the one-loop matching between the Standard Model Effective Field Theory and the low-energy effective field theory below the electroweak scale, where the heavy gauge bosons, the Higgs particle, and the top quark are integrated…

High Energy Physics - Phenomenology · Physics 2022-11-21 Wouter Dekens , Peter Stoffer

In theories of Partial Compositeness the top quark is a mixture of a composite and an elementary state, and as a consequence its interactions with gauge bosons are expected to deviate from those of a point-like object. At sufficiently large…

High Energy Physics - Phenomenology · Physics 2019-08-21 Diogo Buarque Franzosi , Alberto Tonero

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

Top quarks are a prime system for hunting for new physics. Nonetheless, two decades on from their discovery few of their couplings have been measured to high precision. We present an overview of current determinations and the expected…

High Energy Physics - Experiment · Physics 2013-09-17 Jahred Adelman , Matthew Baumgart , Aran Garcia-Bellido , Andrey Loginov

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 study new physics effects to the quartic gauge boson couplings formulated by the electroweak chiral Lagrangian. Five next-to-leading order operators characterize the anomalous quartic gauge interactions which involve pure Goldstone boson…

High Energy Physics - Phenomenology · Physics 2009-10-30 T. Han , H. -J. He , C. -P. Yuan

We compute the effects of anomalous gauge-boson couplings at high-energy hadron colliders using next-to-leading order $SU(2) \times SU(2)$ chiral perturbation theory. By comparing the yields from the universal $p^2$ terms with those arising…

High Energy Physics - Phenomenology · Physics 2009-10-22 J. Bagger , S. Dawson , G. Valencia

The production of three electroweak gauge bosons in high-energy $e^+e^-$ collisions offers a window on anomalous quartic gauge boson couplings. We investigate the effect of three possible anomalous couplings on the cross sections for…

High Energy Physics - Phenomenology · Physics 2011-09-13 W. James Stirling , Anja Werthenbach

The latest results on top quark physics, namely single top quark production cross sections, $W$-boson helicity and asymmetry measurements are used to probe the Lorentz structure of the $Wtb$ vertex. The increase of sensitivity to new…

We investigate the feasibility of probing anomalous top-quark couplings of $Wtb$, $Z t \bar{t}$, and $\gamma t \bar{t}$ in terms of an effective Lagrangian with dimension-six operators at future $e^+e^-$ linear colliders with a c. m. energy…

High Energy Physics - Phenomenology · Physics 2009-11-07 Z. -H. Lin , T. Han , T. Huang , J. -X. Wang , X. Zhang

We advocate an effective field theory approach to anomalous couplings. The effective field theory approach is the natural way to extend the standard model such that the gauge symmetries are respected. It is general enough to capture any…

High Energy Physics - Phenomenology · Physics 2015-06-05 Celine Degrande , Nicolas Greiner , Wolfgang Kilian , Olivier Mattelaer , Harrison Mebane , Tim Stelzer , Scott Willenbrock , Cen Zhang

We study the dimension-6 quark anomalous electroweak couplings in the formulation of linearly realized effective Lagrangian. We investigate the constraints on these anomalous couplings from the $pp \rightarrow W^+W^-$ process in detail at…

High Energy Physics - Phenomenology · Physics 2016-03-30 Sheng-Zhi Zhao , Bin Zhang

Assuming an existence of an anomalous triple electro-weak bosons interaction being defined by coupling constant $\lambda$, we calculate its contribution to interactions of the Higgs with pairs of heavy particles. Bearing in mind…

High Energy Physics - Phenomenology · Physics 2017-08-23 B. A. Arbuzov , I. V. Zaitsev

The anomalous couplings of the top quark and the Higgs boson has been studied in an effective theory resulting in the framework of the minimal supersymmetric extension of the standard model (MSSM) when the heavy fields are integrated out.…

High Energy Physics - Phenomenology · Physics 2009-11-10 Tai-Fu Feng , Xue-Qian Li , Jukka Maalampi