Related papers: Nonstandard, strongly interacting spin one $t \bar…
In recent years, there has been a renewed interest on axigluons as part of a possible extension of strong interactions at high energies. In this work, we use recent ATLAS measurements of the dijet spectrum in order to set limits on the…
We investigate the discovery potential of light color-octet bosons in the mass range of 100 - 400 GeV in exclusive top-pair plus jet production at the LHC. We study the impact of such bosons on the incline, the energy and the rapidity…
Extensions of the Standard Model often predict new chiral interactions for top quark, which will contribute to top quark spin correlation and polarization in $t\bar{t}$ production at the LHC. In this work, under the constraints from the…
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…
Both CDF and DO report a forward-backward asymmetry in t-tbar production that is above the standard model prediction. We review new physics models that can give a large forward backward asymmetry in t-tbar production at the Tevatron and the…
The top forward-backward asymmetry (tAFB) measured at the Tevatron remains one of the most puzzling outstanding collider anomalies. After two years of LHC running, however, few models for tAFB remain consistent with LHC data. In this paper…
The light axigluon model can explain the Tevatron $t\overline{t}$ forward-backward asymmetry and at the same time satisfy the constraints from the electroweak precision measurement and the $ATLAS$ and $CMS$ data, which induces the flavor…
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…
Through top-quark pair productions at LHC, we study possible effects of nonstandard top-gluon couplings yielded by SU(3)xSU(2)xU(1) invariant dimension-6 effective operators. We calculate the total cross section and also some distributions…
Precision electroweak data, a light higgs and LHC searches for new spin one particles are all very constraining on technicolor models. We use a holographic model of walking techicolor (WTC) gauge dynamics, tuned to produce a light higgs and…
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…
We consider new physics explanations of the anomaly in the top quark forward-backward asymmetry measured at the Tevatron, in the context of flavor conserving models. The recently measured LHC dijet distributions strongly constrain many…
In this paper, we study the sensitivity of the fraction of $t\bar{t}$ events arising from gluon-gluon fusion to the chromoelectric and chromomagnetic dipole moments (CEDM and CMDM) as well as the total and differential $t\bar{t}$ cross…
The charge asymmetry in top quark production at hadron colliders is sensitive to beyond-the-Standard-Model four-fermion interactions. In this study we compare the sensitivity of cross-section and charge asymmetry measurements to effective…
The LHC has started to explore the TeV energy regime, probing the SM beyond LEP and Tevatron. We show how the dijet measurements at the LHC are able to test certain sectors of the SM at an unprecedented level. We provide the best bounds on…
We examine the implications of the recent CDF measurement of the top-quark forward-backward asymmetry, focusing on a scenario with a new color octet vector boson at 1-3 TeV. We study several models, as well as a general effective field…
By exploiting the correlation between charge and spin polarisation asymmetries in t-tbar, we show that combining the two observables could identify the presence of quasi-degenerate states in a resonant signal at the LHC. As an example, we…
Many extensions of the Standard Model contain (pseudo)scalar bosons with masses in the TeV range. At hadron colliders, such particles would predominantly be produced in gluon fusion and would decay into top quark pair final sates, a signal…
A critical survey of the existing direct and indirect constraints on massive spin-one color octets is presented. Since such new degrees of freedom appear in any extension of the color gauge group to a product of at least two SU(3) factors,…
Top quark-antiquark ($t\bar t$) pairs will be produced copiously at the Tevatron collider and in huge numbers at the LHC. This will make possible detailed investigations of the properties and interactions of this quark flavor. The analysis…