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We consider how the measurement of top polarization at the Tevatron can be used to characterise and discriminate among different new physics models that have been suggested to explain the anomalous top forward-backward asymmetry reported at…

High Energy Physics - Phenomenology · Physics 2015-03-17 Debajyoti Choudhury , Rohini M. Godbole , Saurabh D. Rindani , Pratishruti Saha

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 anomalous forward-backward asymmetry (A_FB) in t tbar production at the Tevatron is in apparent contradiction with the t tbar charge asymmetry (A_C) measurements at the LHC, which agree well with the standard model predictions. We argue…

High Energy Physics - Phenomenology · Physics 2012-12-04 Jure Drobnak , Alexander L. Kagan , Jernej F. Kamenik , Gilad Perez , Jure Zupan

The forward-backward asymmetry in top pair production at the Tevatron has long been in tension with the Standard Model prediction. One of the only viable new physics scenarios capable of explaining this anomaly is an s-channel axigluon-like…

High Energy Physics - Phenomenology · Physics 2015-06-15 Matthew Baumgart , Brock Tweedie

Axigluons are colored heavy neutral gauge boson that couple to quarks through an axial vector current and the same strong coupling as gluons. The most important model-independent manifestation of axigluons is the generation of a…

High Energy Physics - Phenomenology · Physics 2008-11-26 Oscar Antunano , Johann H. Kuhn , German Rodrigo

The contributions to the cross section $\sigma_{t\bar{t}}$ and to the forward-backward asymmetry $A_{\rm FB}^{t \bar t}$ of $t\bar{t}$ production at the Tevatron from $Z'$-boson and scalar leptoquarks $S^{(\pm)}_a$ and scalar gluons $F_a$…

High Energy Physics - Phenomenology · Physics 2010-10-28 M. V. Martynov , A. D. Smirnov

The top forward-backward asymmetry (FBA) observed at the Tevatron has been a hot issue in particle physics for the last few years. In this talk, I describe two different approaches for the top FBA at the Tevatron, one in effective field…

High Energy Physics - Phenomenology · Physics 2013-01-09 P. Ko

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

We construct flavor-dependent chiral U(1)' models with a Z' boson which couples to the right-handed up-type quarks in the standard model (SM). To make the models have realistic renormalizable Yukawa couplings, we introduce new Higgs…

High Energy Physics - Phenomenology · Physics 2022-03-02 P. Ko , Yuji Omura , Chaehyun Yu

We propose an axigluon with mass between 400 and 450 GeV and flavor universal couplings to quarks to explain the Tevatron t-tbar forward-backward asymmetry. The model predicts a small negative asymmetry for t-tbar pairs with invariant mass…

High Energy Physics - Phenomenology · Physics 2013-05-29 Gustavo Marques Tavares , Martin Schmaltz

A search is presented for charge-asymmetric production of a W' boson that has been proposed to accommodate the forward-backward asymmetry observed in the production of top-antitop quark pairs at the Tevatron. The new heavy W' boson would be…

High Energy Physics - Experiment · Physics 2013-01-29 CMS Collaboration

The recent Tevatron measurement of the forward-backward asymmetry of the top quark shows an intriguing discrepancy with Standard Model expectations, particularly at large $\ttbar$ invariant masses. Measurements of this quantity are subtle…

High Energy Physics - Phenomenology · Physics 2013-05-29 JoAnne L. Hewett , Jessie Shelton , Michael Spannowsky , Tim M. P. Tait , Michihisa Takeuchi

We explore the discovery potential of W' and Z' boson searches for various SU(2) x SU(2) x U(1) models at the Large Hadron Collider (LHC), after taking into account the constraints from low energy precision measurements and direct searches…

High Energy Physics - Phenomenology · Physics 2012-11-14 Qing-Hong Cao , Zhao Li , Jiang-Hao Yu , C. -P. Yuan

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

The CDF collaboration has recently reported a large deviation from the standard model of the t \bar t forward-backward asymmetry in the high invariant mass region. We interpret this measurement as coming from new physics at a heavy scale…

High Energy Physics - Phenomenology · Physics 2015-03-19 Cédric Delaunay , Oram Gedalia , Yonit Hochberg , Gilad Perez , Yotam Soreq

The decay of the Z' boson into supersymmetric particles is studied. We investigate how these supersymmetric modes affect the current limits from the Tevatron and project the expected sensitivities at the LHC. Employing three representative…

High Energy Physics - Phenomenology · Physics 2015-03-19 Chun-Fu Chang , Kingman Cheung , Tzu-Chiang Yuan

We study different top quark charge asymmetries and the variation of $t\bar t$ total cross section induced by the effective axial-vector coupling of gluon in the LHC experiments. We show that rapidity cut-dependent asymmetries are more…

High Energy Physics - Phenomenology · Physics 2012-07-16 Emidio Gabrielli , Antonio Racioppi , Martti Raidal

New colour octets stand out among the new physics proposals to explain the anomalous forward-backward asymmetry measured in $t \bar t$ production by the CDF experiment at the Tevatron. We perform a fit to $t \bar t$ observables at the…

High Energy Physics - Phenomenology · Physics 2015-06-19 J. A. Aguilar-Saavedra

We computed the bottom-quark forward-backward asymmetry at the Tevatron in the Standard Model and for several new physics scenarios. Near the $Z$-pole, the SM bottom asymmetry is dominated by tree level exchanges of electroweak gauge…

High Energy Physics - Phenomenology · Physics 2014-07-14 Benjamín Grinstein , Christopher W. Murphy

We consider the top forward-backward (FB) asymmetry at the Tevatron and top charge asymmetry at the LHC within chiral U(1)^\prime models with flavor-dependent U(1)^\prime charges and flavored Higgs fields, which were introduced in the ref.…

High Energy Physics - Phenomenology · Physics 2015-06-05 P. Ko , Yuji Omura , Chaehyun Yu