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Related papers: Multiscale Technicolor and the Zbb-bar Vertex

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Electroweak Precision Measurements are stringent tests of the Standard Model and sensitive probes to New Physics. Accurate studies of the $Z$-boson couplings to the first-generation quarks, which are currently constrained from LEP data to a…

High Energy Physics - Phenomenology · Physics 2025-11-13 Krzysztof Mękała , Daniel Jeans , Jürgen Reuter , Junping Tian , Aleksander Filip Żarnecki

Technicolor and other theories of dynamical electroweak symmetry breaking invoke chiral symmetry breaking triggered by strong gauge-dynamics, analogous to that found in QCD, to explain the observed W, Z, and fermion masses. In this talk we…

High Energy Physics - Lattice · Physics 2011-05-18 R. Sekhar Chivukula , Elizabeth H. Simmons

We use 106 $\ipb$ of data collected with the Collider Detector at Fermilab to search for narrow-width, vector particles decaying to a top and an anti-top quark. Model independent upper limits on the cross section for narrow, vector…

High Energy Physics - Experiment · Physics 2010-05-12 T. Affolder

I consider the possibility that electroweak symmetry is broken by a strongly interacting chiral gauge theory. I argue that some of the discrepancies between precision electroweak measurements and the predictions of QCD-like technicolor…

High Energy Physics - Phenomenology · Physics 2014-11-17 John Terning

The LHC is a promising machine to discover new physics in the top sector. There are several models that predict the existence of heavy colored resonances decaying to top quarks in the TeV energy range. The production of such resonances…

High Energy Physics - Phenomenology · Physics 2010-11-19 Paola Ferrario , German Rodrigo

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

The topcolor-assisted technicolor (TC2) theory predicts tree-level flavor-changing neutral-current (FCNC) top quark Yukawa couplings with top-pions. Such FCNC interactions will induce like-sign top quark pair productions at CERN Large…

High Energy Physics - Phenomenology · Physics 2008-11-26 Junjie Cao , Guoli Liu , Jin Min Yang

The measurement of forward-backward asymmetry in the top and anti-top quark ($t \bar{t}$) production has been recently reconfirmed by the CDF Collaboration and shows a more than $3\sigma$ deviation from the Standard Model(SM) prediction in…

High Energy Physics - Phenomenology · Physics 2011-05-13 Biplob Bhattacherjee , Sudhansu S. Biswal , Diptimoy Ghosh

We study top quark flavor violation in the framework of a warped extra dimension with the Standard Model (SM) fields propagating in the bulk. Such a scenario provides solutions to both the Planck-weak hierarchy problem and the flavor puzzle…

High Energy Physics - Phenomenology · Physics 2008-11-26 Kaustubh Agashe , Gilad Perez , Amarjit Soni

In the off-diagonal basis, we discuss the contributions of the non-universal gauge boson $Z'$ predicted by the topcolor-assisted technicolor ($TC2$) model to the spin configurations and the spin correlation observable of the top quark pair…

High Energy Physics - Phenomenology · Physics 2008-11-26 Chong-Xing Yue , Li-Na Wang

We establish the existence of the top quark using a 67 pb^-1 data sample of Pbar-P collisions at Sqrt(s) = 1.8 TeV collected with the Collider Detector at Fermilab (CDF). Employing techniques similar to those we previously published, we…

High Energy Physics - Experiment · Physics 2012-08-27 The CDF Collaboration

We explore the top quark flavor-changing 4-Fermi interactions ($tuee$ and $tcee$) with scalar, vector, and tensor structures using machine learning models to analyze tri-lepton processes at the LHC. The study is performed using $t\bar{t}$…

High Energy Physics - Phenomenology · Physics 2025-06-17 Meisam Ghasemi Bostanabad , Mojtaba Mohammadi Najafabadi

The mixing of a new $Z'$ boson with the $Z$ significantly improves the fit to the LEP precision electroweak data, provided that the $Z'$ couples mainly to quarks. If $M_{Z_2}<200$~GeV, the $s$-channel $Z_2$ production and $(W,Z,\gamma)Z_2$…

High Energy Physics - Phenomenology · Physics 2009-09-15 V. Barger , Kingman Cheung , Paul Langacker

We study the constraints on models of topcolor-assisted technicolor arising from measurements of high-$E_T$ jets and high-mass lepton pairs at the Tevatron collider. Existing data can eliminate models that have appeared in the literature.

High Energy Physics - Phenomenology · Physics 2009-10-30 Yumian Su , Gian Franco Bonini , Kenneth Lane

I propose a resolution of the strong CP problem of quarks based on vacuum alignment in theories of dynamically broken electroweak and flavor symmetries. Mixing in the neutral B and K--meson systems is used to restrict the form of quark mass…

High Energy Physics - Phenomenology · Physics 2007-05-23 Kenneth Lane

In the framework of the topcolor-assisted technicolor (TC2) models, we study the productions of a single top or bottom quark associated with a scalar in \gamma-p collision, which proceed via the subprocesses c\gamma -> t\pi_t^0, c\gamma ->…

High Energy Physics - Phenomenology · Physics 2011-02-02 Guo-Li Liu

The mechanism of the electroweak symmetry-breaking (EWSB) is studied in the context of the heavy top quark, whose large mass may provide a clue as to the mechanism which generates the mass of the $W^\pm$ and $Z$ bosons. As a result, it…

High Energy Physics - Phenomenology · Physics 2007-05-23 Tim M. P. Tait

The root of most of the technicolor (TC) problems lies in the way the ordinary fermions acquire their masses, where an ordinary fermion (f) couples to a technifermion (F) mediated by an Extended Technicolor (ETC) boson leading to fermion…

High Energy Physics - Phenomenology · Physics 2020-10-28 A. Doff

We establish the most general parametrization of the new physics tested by present precision measurements and possibly responsible for any deviation of the $Z\to b \bar b $ amplitude from its Standard Model result, under the assumption that…

High Energy Physics - Phenomenology · Physics 2016-09-01 G. J. Gounaris , F. M. Renard , C. Verzegnassi

The dominant electroweak corrections to the production cross sections and partial decay widths of a light Standard-Model Higgs boson, with mass M_H << 2m_t, are due to top-quark loops. By means of a low-energy theorem, we study at the…

High Energy Physics - Phenomenology · Physics 2009-10-30 A. Djouadi , P. Gambino , B. A. Kniehl