English
Related papers

Related papers: $A^t_{FB}$ Meets LHC

200 papers

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 forward-backward asymmetry (FBA) in top-pair production that was observed in 2008 gets a boost in a recent CDF publication. Not only has the FBA further been confirmed, but also distributional preferences are shown. Strikingly, the FBA…

High Energy Physics - Phenomenology · Physics 2015-03-17 Kingman Cheung , Tzu-Chiang Yuan

With the full Tevatron Run II and early LHC data samples, the opportunity for furthering our understanding of the properties of the top quark has never been more promising. Although the current knowledge of the top quark comes largely from…

High Energy Physics - Experiment · Physics 2015-06-03 Kevin Lannon , Fabrizio Margaroli , Chris Neu

Recent CDF and D0 measurements of the top quark forward-backward asymmetry at the Tevatron present deviations between 1-sigma and 2-sigma from QCD predictions and a cut M_inv > 450 GeV on the events increases this deviation to 3.4 sigma in…

High Energy Physics - Phenomenology · Physics 2012-05-29 Davide Pagani

We present a phenomenological analysis of the recent Tevatron results on the $t \bar t$ forward-backward asymmetry and invariant-mass spectrum assuming a new contribution from an s-channel gluon resonance with a mass in the range from 700…

High Energy Physics - Phenomenology · Physics 2011-09-13 Ezequiel Alvarez , Leandro Da Rold , Juan Ignacio Sanchez Vietto , Alejandro Szynkman

The difference in angular distributions between top quarks and antiquarks, commonly referred to as the charge asymmetry, is measured in pp collisions at the LHC with the CMS experiment. The data sample corresponds to an integrated…

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

Several models predict the existence of heavy colored resonances decaying to top quarks in the TeV energy range that might be discovered at the LHC. In some of those models, moreover, a sizable charge asymmetry of top versus antitop quarks…

High Energy Physics - Phenomenology · Physics 2009-02-23 Paola Ferrario , German Rodrigo

First observed in 1995, the top quark is the third-generation up-type quark of the standard model of particle physics (SM). The CDF and D\O\ collaborations have analyzed many \ttbar\ events produced by the Tevatron collider, studying many…

High Energy Physics - Experiment · Physics 2019-08-14 Karolos Potamianos

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

This review summarizes the program in the physics of the top quark being pursued at Fermilab's Tevatron proton-antiproton collider at a center of mass energy of 1.96 TeV. More than a decade after the discovery of the top quark at the two…

High Energy Physics - Experiment · Physics 2009-09-15 Marc-André Pleier

A measurement of the top-antitop ($t\bar{t}$) charge asymmetry is presented using data corresponding to an integrated luminosity of 4.6 fb$^{-1}$ of LHC $pp$ collisions at a centre-of-mass energy of 7 TeV collected by the ATLAS detector.…

High Energy Physics - Experiment · Physics 2015-05-20 ATLAS Collaboration

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

The large cross sections for gauge boson production at the Fermilab Tevatron and the CERN Large Hadron Collider (LHC) might give a chance to determine the electroweak parameters with high precision. We calculated two different…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. Pittau , F. del Aguila , Ll. Ametller

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 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

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 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

In a topcolor-assisted technicolor model (TC2) with large FCNC top quark couplings, we study its correlated contributions to the top quark forward-backward asymmetry ($A_{FB}$) at the Tevatron, the top charge asymmetry ($A_{C}$) and the…

High Energy Physics - Phenomenology · Physics 2015-06-04 Chengcheng Han , Ning Liu , Lei Wu , Jin Min Yang

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

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