Related papers: A New Decoupling Theorem in Top-Quark Physics
We present a comprehensive theoretical framework for probing quantum entanglement in the decay angular distributions of a spin-$S$ particle-antiparticle pair $A\bar{A}$, where each particle decays sequentially into a two-body final state,…
We study the angular distribution of the charged lepton in the top-quark decay into a bottom quark and a W boson which subsequently decays into \ell\nu_{\ell}, when a hard gluon is radiated off. The absorptive part of the t \to bWg decay…
The processes of six-quark production with one $b\bar b$ pair are studied by means of a complete tree-level electroweak calculation. The top-quark signal is examined: the importance of electroweak backgrounds, of the order of 10% above the…
We review the present situation in top quark physics, in these early days of Run II of the LHC. We take mostly a Standard Model perspective, showing recent results, and review the key concepts and results of the associated theoretical…
The case of heavy quark propagation in dense extended matter is studied in the multiple scattering formalism of the higher twist energy loss scheme. We consider the case of deep inelastic scattering off a large nucleus. The hard lepton…
We consider the decay of a polarized top quark into a polarized W-boson plus a bottom quark, followed by the decay of the W-boson into a pair of leptons or quarks. The polar angle distribution of the top spin relative to the W-momentum and…
In this talk I will give an overview on theoretical aspects of top quark physics. The focus lies on top pair production and single top production.
In most of the models beyond the Standard Model, the top quark is expected to be polarized when produced in the decay of some heavier particle, like the gluino or the stop. The polarization is constructed, in an experiment or in…
Analytic formulae are given for QCD corrections to the lepton spectra in decays of polarised up and down type heavy quarks. These formulae are much simpler than the published ones for the corrections to the spectra of charged leptons…
In a general decay chain $A\to B_1B_2\to C_1C_2\ldots$, we prove that the angular correlation function $I(\theta_1,\theta_2,\phi_+)$ in the decay of $B_{1,2}$ is irrelevant to the polarization of the mother particle $A$ at production. This…
Twelve years after the discovery of the Top quark, the CDF detector has collected large samples of tt-bar events with integrated luminosities up to 1-1.7 fb^-1, where we are able to probe our knowledge of the Standard Model Top quark. This…
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…
I will briefly review the status of higher-order calculations for top-quark observables, comment on the need for improvements, discuss some of the recent theoretical advances, and present a few examples to highlight the role of top-quark…
The coefficients determining the dilepton decay angular distribution of vector particles obey certain positivity constraints and a rotation-invariant identity. These relations are a direct consequence of the covariance properties of angular…
The top quark plays an important role in the grand scheme of particle physics, and is also interesting on its own merits. We present recent results from CDF on top-quark physics based on 100-200/pb of p-pbar collision data. We have measured…
We propose to measure the threshold lepton asymmetry, that is the forward-backward asymmetry of the charged lepton in ttbar events near the production threshold. At threshold top quark pairs are produced in an s-wave. Angular momentum…
At the present time, there are hints of new physics (NP) in several observables involving $b \to c \ell^- {\bar\nu}_\ell$ decays. In this talk, I describe measurable angular distributions for ${\bar B} \to D^* \mu^- {\bar\nu}_\mu$ and…
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…
We present the azimuthal correlations in the decay products of the top quark pair created in the process $gg \to t \tbar \to b \bbar \wplus \wminus$ calculated in leading-order QCD. We then discuss deviations in this distribution that could…
We present a systematic comparison of different approaches for the modeling of $t\bar{t}\gamma$ final states with leptonic decays at the LHC. On the one hand, we consider a complete calculation at NLO QCD accuracy which includes all…