相关论文: Explaining the t-tbar asymmetry with a light axigl…
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…
Several recent measurements at the Tevatron experiments point towards an anomalously large forward-backward asymmetry in top-antitop production. This article summarizes the main classes of physics beyond the standard model that can give…
In our latest paper "Search for anomalous top-gluon couplings at LHC revisited" in Eur. Phys. J. C65 (2010), 127-135 (arXiv:0910.3049 [hep-ph]), we studied possible effects of nonstandard top-gluon couplings through the chromoelectric and…
We examine loop-mediated effects of new heavy quarks Q=(t',b') on t tbar production at hadron colliders, using a phenomenological model with flavor off-diagonal couplings of charged and neutral scalars phi=(phi^+-,phi^0) to Q. We show that…
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…
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…
A simple variant of a realistic flavour symmetry scheme for fermion masses and mixings provides a possible interpretation of the diphoton anomaly as an electroweak singlet "flavon". The existence of TeV scale vector-like T-quarks required…
Rapidity gaps between two hard jets at the Tevatron have been interpreted as being due to the exchange of two gluons which are in an overall color-singlet state. We show that this simple picture involves unitarity violating amplitudes.…
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…
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…
The contributions into radiative correction parameters S, T, U from scalar leptoquark and scalar gluon doublets are investigated in the minimal four color symmetry model. It is shown that the existence of the relatively light scalar…
We investigate a charge asymmetry in $t \bar t \gamma$ production at the LHC that provides complementary information to the measured asymmetries in $t \bar t$ production. We estimate the experimental uncertainty in its measurement at the…
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…
A flavor-universal extension of the strong interactions was recently proposed in response to the apparent excess of high-$E_T$ jets in the inclusive jet spectrum measured at the Tevatron. This paper studies the color octet of massive gauge…
We perform a joint analysis of the prediction of composite Higgs models for the discrepancies of the forward-backward asymmetries of top and bottom quarks at Tevatron and LEP+SLC, respectively. We build a two sector model which can be…
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…
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…
The charge asymmetry in t t-bar events is measured using dilepton final states produced in pp collisions at the LHC at sqrt(s) = 8 TeV. The data sample, collected with the CMS detector, corresponds to an integrated luminosity of 19.5…
The ATLAS and CMS experiments at the LHC have found significant excess in the diphoton invariant mass distribution near 750 GeV. We interpret this excess in a predictive nonsupersymmetric SU(5) grand unified framework with a singlet scalar…
The top-antitop quark (t t-bar) production cross section is measured in proton-proton collisions at sqrt(s) = 8 TeV with the CMS experiment at the LHC, using a data sample corresponding to an integrated luminosity of 5.3 inverse femtobarns.…