Related papers: Testing for New Couplings in Top Quark Decay
Overview on top couplings measurements is presented, and the prospects of future measurements are discussed. The coupling of top to the W boson can be examined either by looking at the decay of the top quark or from single top quark…
We discuss possibilities to measure the tt-gamma and ttZ couplings at hadron and lepton colliders. We also briefly describe how these measurements can be used to constrain the parameter space of models of new physics, in particular Little…
The electroweak production and subsequent decay of single top quarks in the $t$-channel is determined by the properties of the $Wtb$ vertex, which can be described by the complex parameters of an effective Lagrangian. An analysis of a…
Recent measurements of top quark properties at the LHC from ATLAS and CMS experiments are presented. The presented results include top quark mass, dependence of top mass measurements on event kinematics, top anti-top mass difference, bottom…
We measure the branching fraction of the top quark to longitudinally and right-handed polarized $W$ bosons, $F_0$ and $F_+$, using approximately 200 pb$^{-1}$ of $\bar{p}p$ collisions collected by the CDF II detector. We analyze two…
With the deeper study of Higgs particle, Higgs precision measurements can be served to probe new physics indirectly. In many new physics models, vector-like quarks $T_L,~T_R$ occur naturally. It is important to probe their couplings with…
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…
This paper investigates a signature of Lorentz invariance violation with the $t\bar{t}$ production at the LHC and future hadron colliders. Possible deviations from the Lorentz symmetry remain poorly constrained in the top quark sector. With…
A precise measurement of the Higgs boson couplings to bottom and top quarks is of paramount importance during the upcoming LHC runs. We present a comprehensive analysis for the Higgs production process in association with a…
We present measurements of the tWb coupling form factors using information from electroweak single top quark production and from the helicity of W bosons from top quark decays in ttbar events. We set upper limits on anomalous tWb coupling…
Highlights of measurements of the properties of the top quark at the LHC are presented. The measurements probe a range of the properties of the top quark, including the structure of the $Wtb$ vertex, the top-Z coupling and the top-quark…
A search is presented for a heavy W' boson resonance decaying to a B or T vector-like quark and a t or a b quark, respectively. The analysis is performed using proton-proton collisions collected with the CMS detector at the LHC. The data…
We study two simple $CP$-violating asymmetries of leptons coming from the decay of $t$ and $\o t$ in $e^+e^- \ra \tt$, which do not need the full reconstruction of the $t$ or $\o t$ for their measurement. They can arise when the top quark…
Tests of quantum properties of fundamental particles in high energy colliders are starting to appear. However, such experiments may suffer from the locality loophole. We argue for criteria that take into account the space-like separation…
Due to the large mass of top quark, CP violation in the top-quark decay is sensitive to the interactions mediated by Higgs bosons. We consider CP violation in $t\rightarrow W^+ b$ decay by calculating consistently in unitary gauge the…
For the observed t --> W b decay, an intensity-ratio equivalence-theorem for two Lorentz-invariant couplings is shown to be related to symmetries of tWb-transformations. Three explicit tWb-transformations, A_{+}=M A_{SM}, ... relate the…
We calculate the density matrix for the decay of a polarised top quark into a polarised W boson and a massive b quark, for the most general Wtb vertex arising from dimension-six gauge-invariant effective operators. We show that, in addition…
Suppose a heavy neutral Higgs or scalar boson $H$ is discovered at the LHC, it is important to investigate its couplings to the standard model particles as much as possible. Here in this work we attempt to probe the CP-even and CP-odd…
For the " t --> W b " decay mode, an intensity-ratio equivalence-theorem for two Lorentz-invariant couplings is shown to be related to symmetries of tWb-transformations. Explicit tWb-transformations, A_{+}=M A_{SM}, P A_{SM}, B A_{SM}…
The ATLAS and CMS collaborations recently announced the observation of the associated production of the Higgs boson with a top quark pair ($t\bar tH$) at the LHC. This process depends directly on the the top quark Yukawa coupling and…