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Related papers: Axigluons cannot explain the observed top quark fo…

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Motivated by recent measurements of the top quark forward-backward asymmetry at the Tevatron, we study how t-channel new physics can contribute to a large value. We concentrate on a theory with an abelian gauge boson possessing flavor…

High Energy Physics - Phenomenology · Physics 2010-04-06 Sunghoon Jung , Hitoshi Murayama , Aaron Pierce , James D. Wells

We explore the possibility that the large $t\bar t$ forward-backward asymmetry measured by the CDF detector at Tevatron could be due to a universal effective axial-vector coupling of gluon. Using an effective field theory approach we show…

High Energy Physics - Phenomenology · Physics 2013-05-29 Emidio Gabrielli , Martti Raidal

Models of top condensation can provide both a compelling solution to the hierarchy problem as well as an explanation of why the top-quark mass is large. The spectrum of such models, in particular topcolor-assisted technicolor, includes…

High Energy Physics - Phenomenology · Physics 2015-05-28 Yanou Cui , Zhenyu Han , Matthew D. Schwartz

The forward-backward asymmetry measurement in top-pair production at the Tevatron is about $2\sigma$ from the Standard Model prediction. We propose an asymmetric left-right model, which includes a $W'$ boson with a right-handed coupling of…

High Energy Physics - Phenomenology · Physics 2014-11-20 Vernon Barger , Wai-Yee Keung , Chiu-Tien Yu

The light axigluon model can explain the Tevatron $t\overline{t}$ forward-backward asymmetry and at the same time satisfy the constraints from the electroweak precision measurement and the $ATLAS$ and $CMS$ data, which induces the flavor…

High Energy Physics - Phenomenology · Physics 2015-06-18 Chong-Xing Yue , Shi-Yue Cao , Qing-Guo Zeng

The measurement of the top forward-backward asymmetry in $\ttbar$ production measured at the Tevatron shows deviation from the Standard Model prediction. A $ u \to t$ transition via a flavor changing $Z^{\prime}$ can explain the data. We…

High Energy Physics - Phenomenology · Physics 2011-10-03 Murugeswaran Duraisamy , Ahmed Rashed , Alakabha Datta

We find constraints on the highest scale of symmetry breaking of a model with gauge symmetry $SU(3)_C \otimes SU(3)_L \otimes U(1)_X$ with heavy neutral leptons in the fermion triplets, calculating the anomalous magnetic moment of the muon…

High Energy Physics - Phenomenology · Physics 2021-03-03 C. E. Alvarez-Salazar , O. L. G. Peres

Recent measurements of the top quark charge asymmetry at Tevatron disfavor the existence of flavor universal axigluons and colorons at 2 sigmas. In this letter we explore the possibility to reconcile the data with these models and use the…

High Energy Physics - Phenomenology · Physics 2009-10-20 Paola Ferrario , German Rodrigo

Several recent measurements at the Tevatron experiments point towards an anomalously large forward-backward asymmetry in top-antitop production. This article summarizes the main classes of physics beyond the standard model that can give…

High Energy Physics - Phenomenology · Physics 2011-08-18 Susanne Westhoff

Measurements of the top quark forward-backward asymmetry performed at the Tevatron suggest that new-physics may be playing a role in t-tbar production. To better understand the source of the asymmetry, recent proposals have called for a…

High Energy Physics - Phenomenology · Physics 2015-05-30 Dilani Kahawala , David Krohn , Matthew J. Strassler

We determine the dominant missing Standard Model (SM) contribution to the top quark pair forward-backward asymmetry at the Tevatron. Contrary to past expectations, we find a large, around 27%, shift relative to the well-known value of the…

High Energy Physics - Phenomenology · Physics 2015-07-30 Michal Czakon , Paul Fiedler , Alexander Mitov

The interaction of bottom squark-mediated top quark pair production, occurring in the R-parity violating minimal supersymmetric standard model (MSSM), is proposed as an explanation of the anomalously large $t\bar{t}$ forward-backward…

High Energy Physics - Phenomenology · Physics 2015-06-05 Grace Dupuis , James M. Cline

The most recent measurements at Tevatron of the charge asymmetry in top-antitop quark pair production reduce the discrepancy with the Standard Model from 2sigma to 1.7sigma, and open a little window, at 95% C.L., for negative contributions…

High Energy Physics - Phenomenology · Physics 2022-03-02 German Rodrigo , Paola Ferrario

The light axigluon model of Tavares and Schmaltz is a viable candidate to explain the Tevatron t-tbar forward-backward asymmetry. In this paper we present the forward-backward asymmetries for b-bbar and c-cbar systems predicted by the light…

High Energy Physics - Phenomenology · Physics 2013-07-09 Seyda Ipek

The CDF and D0 experiments at the Fermilab Tevatron have measured the asymmetry between yields of forward- and backward-produced top and antitop quarks based on their rapidity difference and the asymmetry between their decay leptons. These…

High Energy Physics - Experiment · Physics 2018-01-31 CDF collaboration , D0 collaboration

The axial anomaly arising from the fermion sector of $\U(N)$ or $\SU(N)$ reduced model is studied under a certain restriction of gauge field configurations (the ``$\U(1)$ embedding'' with $N=L^d$). We use the overlap-Dirac operator and…

High Energy Physics - Lattice · Physics 2009-11-10 Teruaki Inagaki , Yoshio Kikukawa , Hiroshi Suzuki

Among different measured observables of top-antitop quark pairs at hadron colliders, the forward-backward asymmetry ($A_{\text{FB}}$) measured by the CDF and D0 collaborations has inconsistency with the Standard Model prediction. The…

High Energy Physics - Phenomenology · Physics 2013-02-21 Sara Khatibi , Mojtaba Mohammadi Najafabadi

In the framework of a complete vector-like and universal gauged SU(3)_F family symmetry, we report a global region in the parameter space where this approach can account for a realistic spectrum of quark masses and mixing in a 4 x 4…

High Energy Physics - Phenomenology · Physics 2016-12-23 Albino Hernandez-Galeana

Motivated by the persistence of a large measured top quark forward-backward asymmetry at the Tevatron, we examine a model of non-Abelian flavor gauge symmetry. The exchange of the gauge bosons in the $t$-channel can give a large asymmetry…

High Energy Physics - Phenomenology · Physics 2011-07-05 Sunghoon Jung , Aaron Pierce , James D. Wells

We compute, for top quark pair production at the Tevatron and the Large Hadron Collider, the collider-independent forward-backward asymmetries defined in [1] in the standard model at next-to-leading order in QCD, including also…

High Energy Physics - Phenomenology · Physics 2013-05-30 J. A. Aguilar-Saavedra , W. Bernreuther , Z. -G. Si