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Related papers: Tracking Down the Top Quark Forward-Backward Asymm…

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Forward-backward asymmetries $A_{FB}^t$ and $A_{FB}^\ell$ are observed in the top quark $t$ rapidity distribution and in the rapidity distribution of charged leptons $\ell$ from top quark decay at the Tevatron proton-antiproton collider,…

High Energy Physics - Phenomenology · Physics 2013-01-23 Edmond L. Berger

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

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

We make use of recent results in effective theory and higher-order perturbative calculations to improve the theoretical predictions of the QCD contribution to the top-quark pair production forward-backward asymmetry at the Tevatron. In…

High Energy Physics - Phenomenology · Physics 2013-05-29 Valentin Ahrens , Andrea Ferroglia , Matthias Neubert , Ben D. Pecjak , Li Lin Yang

We calculate the forward backward asymmetry of the top-pair production at TEVATRON up to next to leading order (NLO) in the little Higgs model (LHM). We find that the contribution of $Z_H$ can be large enough to make up the gap between…

High Energy Physics - Phenomenology · Physics 2013-09-24 Xing-Dao Guo , Yin-Jie Zhang , Shu-Min Zhao , Tai-Fu Feng , Xu-Hao Yuan , Xue-Qian Li

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

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

Both D0 and CDF at Tevatron reported the measurements of forward-backward asymmetry in top pair production, which showed possible deviation from the standard model QCD prediction. In this paper, we explore how to examine the {\em same}…

High Energy Physics - Phenomenology · Physics 2011-02-01 You-kai Wang , Bo Xiao , Shou-hua Zhu

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 charge asymmetry in hadronic top-antitop-quark production is a powerful test observable of perturbative quantum chromodynamics. Since its origin in terms of Feynman diagrams is distinct from charge-symmetric top-antitop production,…

High Energy Physics - Phenomenology · Physics 2015-01-30 Susanne Westhoff

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

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 Tevatron has measured a discrepancy relative to the Standard Model prediction in the forward-backward asymmetry in top quark pair production. This asymmetry grows with the rapidity difference of the two top quarks. It also increases…

High Energy Physics - Phenomenology · Physics 2013-05-30 Sudhansu S. Biswal , Subhadip Mitra , Rui Santos , Pankaj Sharma , Ritesh K. Singh , Miguel Won

We review the asymmetries in top quark pair production at the Tevatron and the LHC. We summarize the experimental measurements and the interpretations of a possible excess in terms of new physics. We also review other top quark…

High Energy Physics - Phenomenology · Physics 2015-06-11 J. A. Aguilar-Saavedra , D. Amidei , A. Juste , M. Perez-Victoria

We provide a qualitative and quantitative unified picture of the charge asymmetry in top quark pair production at hadron colliders in the SM and summarise the most recent experimental measurements.

High Energy Physics - Phenomenology · Physics 2014-11-19 Johann H. Kuehn , German Rodrigo

The recent forward-backward asymmetry recorded by the CDF Collaboration for the top and anti-top quark pair production indicates more than $2\sigma$ deviation from the Standard Model prediction, while its total production cross section…

High Energy Physics - Phenomenology · Physics 2009-12-04 Kingman Cheung , Wai-Yee Keung , Tzu-Chiang Yuan

We present a measurement of forward-backward asymmetry in top quark-antiquark production in proton-antiproton collisions in the final state containing a lepton and at least four jets. Using a dataset corresponding to an integrated…

High Energy Physics - Experiment · Physics 2012-08-27 D0 Collaboration

The assumption of a new symmetry provides a nice explanation of the existence of dark matter and an elegant way to avoid the electroweak constraints. This symmetry often requires the pair production of new particles at colliders and it…

High Energy Physics - Phenomenology · Physics 2008-11-26 Kyoungchul Kong , Seong Chan Park

Top quark pair production at proton-antiproton colliders is known to exhibit a forward-backward asymmetry due to higher-order QCD effects. We explore how this asymmetry might be studied at the Fermilab Tevatron, including how the asymmetry…

High Energy Physics - Phenomenology · Physics 2014-11-18 M. T. Bowen , S. D. Ellis , D. Rainwater

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