Related papers: Helicity Amplitudes for Single-Top Production
We describe the implementation of top production and decay processes in the parton-level Monte Carlo program MCFM. By treating the top quark as being on-shell, we can factorize the amplitudes for top-pair production, s-channel single-top…
In this paper, we show how to calculate analytically the one-loop helicity amplitudes for the process $q\bar{q} rightarrow t\bar{t}$ induced by KK gluon, using the spinor-helicity formalism. A minimal set of Feynman rules which are uniquely…
The self-couplings of the electroweak gauge bosons are probed at hadron colliders through the production of a massive gauge boson and a photon. To extend the theoretical description of this type of final states towards…
The production of top quarks in single mode at future ep colliders is studied, the attention being mainly focused to the case of the proposed LEPXLHC collider. We are motivated to reanalyse such a process following the discovery of the top…
We present the complete two-loop corrections in massless QCD for the production of two photons and a jet, taking into account all color structures. In particular, we analytically compute all two-loop helicity amplitudes for the…
The modularity property of the helicity formalism is used to provide amplitude expressions and stage-two spin-correlation functions which can easily be used in direct experimental searches for electro-weak symmetries and dynamics in the…
Recent measurements of top-quark production at hadron colliders are reviewed. The inclusive top-quark pair production is determined at four centre-of-mass energies at Tevatron and LHC with experimental uncertainties that are close to the…
High-energy photon-proton interactions at the LHC offer interesting possibilities for the study of the electroweak sector up to TeV scale and searches for processes beyond the Standard Model. An analysis of the W associated single top…
As continuation of our previous paper we further develop our new method for calculating helicity amplitudes of jet-like QED processes described by tree diagrams, applying it to lepton pair production. This method consists in replacing…
I discuss the calculation of cross sections for processes with six and eight fermions in the final state, contributing to single-top production and associated top-Higgs production at a linear collider. I describe the schemes for the…
The CMS experiment has measured the electroweak production of top quark in different singly production modes: t-, tW- and s-channel. Recent results on inclusive and differential cross section measurements of t-channel at 13 TeV and of the…
This talk concerns some theoretical patterns of the helicity amplitudes for t --> W b decay. The patterns involve both the standard model's four decay helicity amplitudes, A_{SM}, and also the amplitudes A_{+} in the case of an additional…
Single top production processes are usually regarded as the ones in which V_tb can be directly measured at hadron colliders. We show that the analysis of the single top rapidity distribution in t-channel and tW production can also set…
We present a measurement of the helicity of the W boson produced in top quark decays using \ttbar ~decays in the $\ell+$jets and dilepton final states selected from a sample of 5.4 fb$^{-1}$ of collisions recorded using the D0 detector at…
We present compact analytic expressions for all one-loop helicity amplitudes contributing to ttbar production at hadron colliders. Using recently developed generalised unitarity methods and a traditional Feynman based approach we produce a…
This article reports on recent searches for single-top-quark production by the CDF collaboration at the Tevatron using a data set that corresponds to an integrated luminosity of 955 pb^-1. Three different analyses techniques are employed,…
Different measurements of the properties of the top quark using up to $5.4 fb^{-1}$ collected with the D{\O} detector at the Fermilab Tevatron collider are presented. The top mass is obtained from a study of dilepton and lepton+jets final…
We present the most recent measurements of single top quark production cross section by the CDF and D0 experiments at the Fermilab Tevatron Collider and the ATLAS and CMS experiments at the Large Hadron Collider (LHC). The data were…
Due to the absence of hadronization effects and the large top mass, top quark decay will be uniquely sensitive to fundamental electroweak physics at the Tevatron, at the LHC, and at a future linear collider. A complete measurement of the…
With a high instantaneous luminosity and the large top quark pair production cross section, the Large Hadron Collider (LHC) will be a "top factory" allowing the analysis of millions of top events. After a short description of the top quark…