Related papers: Spin Issues in t-tbar Production and Decay
A comparison is made between the off-diagonal and helicity spin bases for top quark pair production at the FNAL Tevatron. In the off-diagonal basis, 92% of the top quark pairs are in the spin configuration up-down plus down-up, whereas in…
We discuss top quark production and its subsequent decay at lepton colliders including both QCD corrections and anomalous gamma / Z - t t-bar couplings. The off-diagonal spin basis for the top and anti-top quarks is shown to be useful to…
We show how to observe sizable angular correlations between the decay products of the top quark and those of the anti-top quark in top quark pair production and decay at hadron colliders. These correlations result from the large asymmetry…
Top-antitop quark pairs produced at the Tevatron have a sizeable spin correlation. That correlation feeds into the angular distribution of the decay products, particularly in the dilepton channel. Including the expected correlation in an…
We discuss the optimal spin bases for describing angular correlations in single top quark events at the Fermilab Tevatron. We define spin bases that exploit the fact that the top quarks are produced with 100% polarization along the momenta…
We propose techniques to observe the correlation of the spins of top quarks and antiquarks at the Tevatron and the LHC. Observation of the spin correlation would confirm that the top quark decays before its spin flips, and would place a…
We show in single top quark production that the spin of the top quark is correlated with the direction of the d-type quark in the event. For single top production in the W* channel, the d-type quark comes dominantly from the antiproton at…
We present the full O(alpha_s) longitudinal spin-spin correlations for heavy-quark pair production at e+ e- high-energy colliders in closed analytical form. In such reactions, quark and antiquark have strongly correlated spins, and the…
Top-antitop pairs produced at hadron colliders are largely unpolarized, but their spins are highly correlated. The structure of these correlations varies significantly over top production phase space, allowing very detailed tests of the…
The object of this thesis is to study the spin-spin correlations for top quark productions and their decay at polarized e^+e^- linear colliders. For the analyses of the spin-spin correlations in top quark production, we introduce a generic…
We discuss top quark production and its subsequent decay for searching new physics at lepton colliders. The angular dependence of the decay leptons is calculated including both QCD corrections and anomalous gamma Z - t tbar couplings. The…
The weak decay of a polarized top quark has a rich structure of angular correlations among its decay products. We describe some of the noteworthy features of such decays. We then examine the three modes of single top production, with an…
We compare theoretical expectations for the observation of spin correlations in top quark pair production and decay at the Fermilab Tevatron and the CERN Large Hadron Collider (LHC). In particular, we note that the differing top quark pair…
A measurement of spin correlation in $t\bar{t}$ production is presented using data collected with the ATLAS detector at the Large Hadron Collider in proton-proton collisions at a center-of-mass energy of 8 TeV, corresponding to an…
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…
An analysis of the spin correlation effects in top quark pair production at hadron colliders is presented with special emphasis for the Large Hadron Collider (LHC). At the LHC top quark pair production is dominated by gluon-gluon fusion.…
We investigate a number of observables that are and will be instrumental in the exploration of $\tbart$ production and decay at the Tevatron and the LHC. For this analysis we made a computer program that incorporates besides the NLO QCD…
Top spin correlation has been shown to be nontrivial in hadronic top-pair production, and can be realized by the asymmetries of the decay products of the top quark and antiquark. We show in this work that the top spin correlation is a…
The top quark decays before it hadronizes. Before its spin state can be changed in a process of strong interaction, it is directly transferred to the top quark decay products. The top quark spin can be deduced by studying angular…
Top quark pairs are produced with strongly correlated spins in the partonic reactions $q\bar{q}\to t\bar{t}$ and $gg\to t\bar{t}$. A complete description of these effects in terms of the spin density matrix of the $t\bar{t}$ system in…