Related papers: Anomalous Wtb coupling at the LHC
The latest results on top quark physics, namely single top quark production cross sections, $W$-boson helicity and asymmetry measurements are used to probe the Lorentz structure of the $Wtb$ vertex. The increase of sensitivity to new…
We study possible anomalous top-quark couplings generated by SU(2) x U(1) gauge invariant dimension-6 effective operators, using the final b-quark momentum distribution in gamma gamma -> tt -> bX. Taking into account non-standard tt gamma,…
The potential of ep collision to prospect for anomalous Wtb vertex is discussed from the single top quark production process $ep\to t\bar{\nu}+X$ for TESLA+HERAp and CLIC+LHC energies. Sensitivities to anomalous couplings $F_{2L}$ and…
We present new direct constraints on a general $Wtb$ interaction using data corresponding to an integrated luminosity of 5.4 fb$^{-1}$ collected by the D0 detector at the Tevatron $p\bar{p}$ collider. The standard model provides a purely…
Kinematical distributions of decay products of the top quark carry information on the polarisation of the top as well as on any possible new physics in the decay of the top quark. We construct observables in the form of asymmetries in the…
A next-to-leading log calculation of the reactions $pp$ and $p\overline{p}\rightarrow W^\pm\gamma X$ is presented including a tri-boson gauge coupling from non-Standard Model contributions. Two approaches are made for comparison. The first…
In an effective operator approach, the full set of leading contributions to anomalous top couplings comprises various new trilinear as well as higher interaction vertices, some of which are related to one another by gauge symmetry or…
W bosons produced at high transverse momentum in hadron collisions can have polarization along the direction perpendicular to the production plane, which is odd under na$\ddot{\i}$ve-T-reversal where both the three-momenta and angular…
We present a detailed study of the anomalous top quark production with subsequent decay at the LHC induced by model-independent flavor-changing neutral-current couplings, incorporating the complete next-to-leading order QCD effects. Our…
Many new physics models beyond the standard model ($SM$) can give rise to the large anomalous top couplings $tqg$ ($q=u$ and $c$). We focus our attention on these couplings induced by the topcolor-assisted technicolor ($TC2$) model and the…
The latest and most precise top quark measurements at the LHC and Tevatron are used to establish new limits on the $Wtb$ vertex. Recent results on the measurements of the $W$-boson helicity fractions and single top quark production cross…
The vector boson scattering (VBS) processes in Large Hadron Collider (LHC) experiments offer a unique opportunity to probe the anomalous quartic gauge couplings (aQGCs). We study the dimension-8 operators contributing to the anomalous…
We study momentum distributions of the final-state charged lepton in ppbar/pp --> ttbar --> l^+ X (l=e or mu) at hadron colliders, i.e., Tevatron and Large Hadron Collider (LHC) in order to explore possible new-physics effects in the…
We study the LHC associated production of a Higgs boson and a W^+W^- vector-boson pair at 14 TeV, in the Standard Model and beyond. We consider different signatures corresponding to the cleanest H and W decay channels, and discuss the…
As a top-factory, the LHC is performing a direct study of top-quark anomalous FCNC couplings, which are, however, correlated closely with the rare B- and K-meson decays. In this paper, we study the effects of anomalous $tqZ$ (with $q=u,c$)…
Considering the present limits on the masses of fourth family quarks from the Tevatron experiments, the fourth family quarks are expected to have mass larger than the top quark. Due to their expected large mass they could have different…
We present measurements of lepton (l) angular distributions in ttbar -> W+ b W- b -> l+ nu b l- nubar bbar decays produced in ppbar collisions at a center-of-mass energy of sqrt(s)=1.96TeV, where l is an electron or muon. Using data…
The angular and energy distributions of the final lepton in e ebar t tbar --> l^{+-} X at next linear colliders (NLC) are analyzed a model-independent way for arbitrary longitudinal beam polarizations as sensitive tests of possible…
The forward-backward asymmetry $A_{FB}^{t\bar t}$ in top quark production at the Tevatron has been observed to be anomalously large by both CDF and D0. It has been suggested that a model with a $W'$ coupling to $td$ and $ub$ might explain…
The production of $\nu \bar{\nu} \gamma \gamma$ in high-energy $e^+e^-$ collisions offers a window on anomalous quartic gauge boson couplings. We investigate the effect of two possible anomalous couplings on the cross section for $\nu…