Related papers: Probing anomalous Wtb couplings in top pair decays
We introduce a new asymmetry in the decay t -> W b -> l nu b, which is shown to be directly proportional to the polarisation of the top quark along a chosen axis, times a sum of W helicity fractions. The latter have already been precisely…
The measurement of quantum entanglement can provide a new and most sensitive probe to physics beyond the Standard Model. We use the concurrence of the top-quark pair spin states produced at colliders to constrain the magnetic dipole term in…
We investigate the possibility that an imaginary anomalous $tbW$ coupling can be measured in the process $e^-p \to \nu_e \overline t X$ by means of T-odd observables. One such observable considered here is the polarization of the top…
We present a study of the experimental determination of the forward-backward asymmetry in the process $e^+e^-\to t\bar t$ and in the subsequent $t\to Wb$ decay, studied in the context of the International Linear Collider. This process…
With data collected during the first half of 2011 pp run of the Large Hadron Collider at \surds = 7 TeV, a substantial data sample of high p_T triggers, 1.08/fb, has been collected by the ATLAS detector. Measurements of the production of…
Analytic expressions for the angular distributions of the $b$-quarks associated with single $t$-quark production in $p \bar p \to W^* \to t \bar b \to b \bar b W$ and of the leptons from the subsequent decay $W \to l\nu$ are obtained in the…
Both ATLAS and CMS have recently performed the first searches for a heavy new spin-0 resonance decaying into a lighter new spin-0 resonance and a $Z$ boson, where the lighter spin-0 resonance subsequently decays into $t \bar t$ pairs. These…
We study the accuracy with which the lowest order $CP$ conserving anomalous $Wtb$ couplings in the single top quark production at the proposed large hadron electron collider (LHeC) can be probed. The one dimensional distribution of various…
An optimal-observable analysis of the angular and energy distributions of the leptons and bottom quarks in the process e+e- --> tt-bar --> l^{+-}/b(b-bar)... has been performed in order to measure the most general top-quark couplings to…
Quantum tomography in high-energy physics processes has usually been restricted to the spin degrees of freedom. We address the case of top quark decays $t \to W b$, in which the orbital angular momentum ($L$) and the spins of $W$ and $b$…
We describe the off-diagonal spin basis for observing angular correlations in top quark pair production events at the Fermilab Tevatron. For events initiated by quark-antiquark annihilation, the top and antitop quark spins are 100%…
Focusing attention on top-quark pair production and its decay processes at the LHC, non-standard top-quark couplings are studied based on the effective Lagrangian constructed with SU(3)X SU(2)X U(1) invariant dimension-6 operators. The…
We present a study of experimental determination of the Wtb anomalous couplings in the $t\bar{t}$ process at the International Linear Collider in the framework of effective field theory. The theory predicts several observables that are…
We study top quark pair production in association with a Z boson at the Large Hadron Collider (LHC) and investigate the prospects of measuring the couplings of top quarks to the Z boson. To date these couplings have not been constrained in…
An overview of the recent measurements of the top quark properties in proton antiproton collisions at \sqrt{s}=1.96 TeV is presented.These measurements are based on 5.4 -- 8.7 fb^-1 of data collected with the D0 and CDF experiments at the…
In order to observe a signal of possible CP violation in top-quark couplings, we study top-quark production and decay under the conditions of the Tevatron upgrade. Transverse energy asymmetries sensitive to CP violation are defined.…
We consider hadronic top quark pair production and pair production in association with a photon or a $Z$ boson to probe electroweak dipole couplings in $t\bar{b}W$, $t\bar{t}\gamma$ and $t\bar{t}Z$ interactions. We demonstrate how…
A review of recent combinations of top-quark measurements performed at the LHC, by the ATLAS and CMS collaborations, is provided. The typical uncertainty categorisations, and their assumed correlation patterns are presented, together with…
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…
In top-pair events where at least one of the tops decays semi-leptonically, the identification of the lepton charge allows to tag not only the top charge but also that of the subsequent b quark. In cases where the b also decays…