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Related papers: Top Quark Asymmetries and Unparticle Physics

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In light of the recent measurements of the top quark forward-backward asymmetry at the Fermilab Tevatron experiment, which in some regions of the parameter space shows a discrepancy of 3$\sigma$ compared to the SM prediction, we analyze top…

High Energy Physics - Phenomenology · Physics 2013-05-29 Mariana Frank , Alper Hayreter , Ismail Turan

The forward-backward asymmetry $A_{FB}$ in top quark pair production, measured at the Tevatron, is probably related to the contribution of new particles. The Tevatron result is more than a $2\sigma$ deviation from the standard model…

High Energy Physics - Phenomenology · Physics 2011-03-21 E. Ramirez Barreto , Y. A. Coutinho , J. Sá Borges

Heavy flavour production at hadron colliders represents a very promising field to test perturbative QCD. The integrated forward-backward asymmetry of the top-antitop quark production is particularly sensitive to any deviation from the…

General Physics · Physics 2013-04-12 Davor Palle

We study contributions of a scalar diquark particle in a color representation of anti-triplet and sextet to the top quark pair production at the Tevatron and the Large hadron collider (LHC). The model can give Forward-Backward (FB)…

High Energy Physics - Phenomenology · Physics 2015-06-05 Kaoru Hagiwara , Junya Nakamura

The forward-backward asymmetry A_{FB}^t in top quark production at the Tevatron has been seen to be anomalously large both by CDF and D0. Parton-level asymmetries as large as 50%, with a large error bar, have been extracted from the data.…

High Energy Physics - Phenomenology · Physics 2011-02-04 Matthew J. Strassler

CDF has observed a top forward-backward asymmetry discrepant with the Standard Model prediction at 3.4 \sigma. We analyze models that could generate the asymmetry, including flavor-violating W's, horizontal Z'_Hs, triplet and sextet…

High Energy Physics - Phenomenology · Physics 2015-03-19 Moira I. Gresham , Ian-Woo Kim , Kathryn M. Zurek

At the LHC, top quark pairs are dominantly produced from gluons, making it difficult to measure the top quark forward-backward asymmetry. To improve the asymmetry measurement, we study variables that can distinguish between top quarks…

High Energy Physics - Phenomenology · Physics 2015-05-28 Yang Bai , Zhenyu Han

Recent experimental results from the CDF collaboration which study the top forward-backward asymmetry have strengthened the case that new physics is playing a role in t-tbar production. Here we propose a set of measurements, built from the…

High Energy Physics - Phenomenology · Physics 2013-05-29 David Krohn , Tao Liu , Jessie Shelton , Lian-Tao Wang

The anomaly of the top quark forward-backward asymmetry $A^t_{FB}$ observed at the Tevatron can be explained by the t-channel exchange of a neutral gauge boson (Z') which has sizable flavor changing coupling for top and up quarks. This…

High Energy Physics - Phenomenology · Physics 2013-05-29 Junjie Cao , Lin Wang , Lei Wu , Jin Min Yang

We present a new measurement of the inclusive forward-backward t-tbar production asymmetry and its rapidity and mass dependence. The measurements are performed with 5.3 fb^{-1} of p-pbar collisions at \sqrt{s} = 1.96 TeV, recorded with CDF…

High Energy Physics - Experiment · Physics 2011-06-24 The CDF Collaboration , T. Aaltonen

The measured forward-backward asymmetry in top pair events at the Fermilab Tevatron collider deviates significantly from the standard model expectation. Several models have been proposed to describe the observed asymmetry which grows with…

High Energy Physics - Phenomenology · Physics 2012-10-25 Seyed Yaser Ayazi , Sara Khatibi , Mojtaba Mohammadi Najafabadi

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

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

The latest measurements of the asymmetry in the angular distributions of the $t\bar{t}$ events are reviewed. The measurements of the forward-backward asymmetry $A_{FB}$ in the $p\bar{p}$ 1.98 TeV collision at the Tevatron show some tension…

High Energy Physics - Experiment · Physics 2013-12-03 Viatcheslav Sharyy

We propose two new observables to measure the charge asymmetry in hadronic top-quark pair production in association with a hard jet. The incline asymmetry, based on the inclination between the planes of initial- and final-state momenta,…

High Energy Physics - Phenomenology · Physics 2013-09-27 Stefan Berge , Susanne Westhoff

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

In order to explain the Tevatron anomaly of the top quark forward-backward asymmetry $A_{FB}^t$ in the left-right twin Higgs model, we choose to give up the lightest neutral particle of $\hat{h}$ field as a stable dark matter candidate.…

High Energy Physics - Phenomenology · Physics 2013-05-30 Lei Wang , Lei Wu , Jin Min Yang

We study and constrain the parameter space of the vector color-octet model from observed data at Tevatron by studying top quark pair production and associated observables afbt and spin-correlation. In particular we study invariant mass and…

High Energy Physics - Phenomenology · Physics 2013-07-09 Sukanta Dutta , Ashok Goyal , Mukesh Kumar

Copious production of top-antitop quark pairs at hadron colliders has enabled various probes into the properties and interactions of top quarks. Among the various presently measured observables, the forward-backward asymmetry (FBA) in t…

High Energy Physics - Phenomenology · Physics 2015-03-20 Svjetlana Fajfer , Jernej F. Kamenik , Blazenka Melic

The top quark forward-backward asymmetry measured at the Fermilab Tevatron collider deviates from the standard model prediction. A W^prime boson model is described, where the coupling W^prime-t-d is fixed by the tt_bar forward-backward…

High Energy Physics - Phenomenology · Physics 2015-06-04 Daniel Duffty , Zack Sullivan , Hao Zhang