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Related papers: Charge asymmetries of top quarks at hadron collide…

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We present updated predictions for the total production cross section of top-quark pairs at the Tevatron and at the LHC, and, at the LHC, of heavy-quark pairs with mass in the range 0.5-2 TeV. For t\bar{t} production at the LHC we also…

High Energy Physics - Phenomenology · Physics 2009-05-08 Matteo Cacciari , Stefano Frixione , Michelangelo L. Mangano , Paolo Nason , Giovanni Ridolfi

We suggest a new possibility for ATLAS and CMS to explore the t-tbar forward-backward asymmetry measured at the Tevatron, by attempting to reconstruct t-tbar events, with one of the tops decaying semileptonically in the central region…

High Energy Physics - Phenomenology · Physics 2011-12-06 Jean-François Arguin , Marat Freytsis , Zoltan Ligeti

We define a lepton-based asymmetry in semi-leptonic ttbar production at the LHC. We show that the ratio of this lepton-based asymmetry and the ttbar charge asymmetry, measured as a function of the lepton transverse momentum or the ttbar…

High Energy Physics - Phenomenology · Physics 2015-06-18 Adrian Carmona , Mikael Chala , Adam Falkowski , Sara Khatibi , Mojtaba Mohammadi Najafabadi , Gilad Perez , Jose Santiago

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

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

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 top quark forward-backward asymmetry A_{FB}^t measured at the Tevatron is above the Standard Model prediction by more than 2-sigma deviation, which might be a harbinger for new physics. In this work we examine the contribution to…

High Energy Physics - Phenomenology · Physics 2010-04-06 Junjie Cao , Zhaoxia Heng , Lei Wu , Jin Min Yang

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

We derive generic predictions at hadron colliders from the large forward-backward asymmetry observed at the Tevatron, assuming the latter arises from heavy new physics beyond the Standard Model. We use an effective field theory approach to…

High Energy Physics - Phenomenology · Physics 2013-01-15 Cédric Delaunay , Oram Gedalia , Yonit Hochberg , Yotam Soreq

We study how the significance of top quark induced charge asymmetries at the LHC may be enhanced exploiting the $t\bar t$ total transverse momentum to enrich the fraction of quark fusion events in the sample. We combine this variable with…

High Energy Physics - Phenomenology · Physics 2013-05-30 Ezequiel Alvarez

With the next start of LHC, a huge production of top quarks is expected. There are several models that predict the existence of heavy colored resonances decaying to top quarks in the TeV energy range. A peak in the differential cross…

High Energy Physics - Phenomenology · Physics 2009-09-02 Paola Ferrario , German Rodrigo

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 2014-03-11 Edmond L. Berger , Qing-Hong Cao , Chuan-Ren Chen , Hao Zhang

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

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 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

The charge asymmetry in top quark pair production in the di-lepton $t\bar t$ channel using the ATLAS experiment at Large Hadron Collider is presented. The asymmetry is studied in the distribution of absolute rapidity difference between top…

High Energy Physics - Experiment · Physics 2012-12-04 Jakub Cúth

The scalar partners of top and bottom quarks are expected to be the lightest squarks in supersymmetric theories, with potentially large cross sections at hadron colliders. We present predictions for the production of top and bottom squarks…

High Energy Physics - Phenomenology · Physics 2014-11-21 Wim Beenakker , Silja Brensing , Michael Krämer , Anna Kulesza , Eric Laenen , Irene Niessen

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

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

The top-antitop energy asymmetry is a promising observable of the charge asymmetry in jet-associated top-quark pair production at the LHC. We present new predictions of the energy asymmetry in proton-proton collisions at 13 TeV, including…

High Energy Physics - Phenomenology · Physics 2017-03-01 Stefan Berge , Susanne Westhoff