相关论文: Measuring Top Quark Polarization in Top Pair plus …
We discuss the determination of polarized parton distributions from a next-to-leading order analysis of recent experimental data. We extract the first moment of the polarized quark and gluon distribution and assess the corresponding…
We review the physics involved in the production and decay of top quarks in e^+e^- -> ttbar near threshold, with special emphasis on the recent theoretical study on the decay process of top quarks in the threshold region. The energy-angular…
In this article, we study top quark pair charge, energy and incline asymmetry at parton level using Powheg Monte-Carlo generator.
Partial top quark compositeness is a crucial aspect of theories with strong electroweak symmetry breaking. Together with the heavy top partners that lift the top quark mass to its observed value, these theories predict correlated…
This study investigates the influence of the fourth generation quarks on the double lepton polarizations in \Lambda_b --> \Lambda \ell^+ \ell^- decay by taking |V^\ast_{t's}V_{t'b}|= 0.005,0.01,0.02,0.03 with phase…
It is anticipated that a number of techniques to measure the top quark mass at the LHC will yield m_top with uncertainties of about 0.5-1 percent. These uncertainties are mostly theoretical; they are usually estimated using parton shower…
The process of top-quark pair production at future high-energy $e^+ e^-$ linear colliders has been investigated as a possible test of physics beyond the Standard Model. Non-standard interactions have been assumed both for the production and…
We investigate the degree of spin polarization of single top quarks in the $e\gamma$ collision via the process $e^{+} \gamma \to t \bar{b} \bar{\nu_{e}}$ with center of mass energies $\sqrt{s}$=0.5, 1 and 1.5 TeV of the parental linear…
Measurements of polarized electron-nucleon scattering can be realized at the TESLA linear collider facility with projected luminosities that are about two orders of magnitude higher than those expected of other experiments at comparable…
Data on the nucleon spin structure suggests that the $u$ (and $d$) quark distributions in the $\Lambda$ hyperon may be polarized. If this correlation carries over into fragmentation, then the study of polarized $\Lambda$'s in the current…
A measurement of the top quark electric charge is carried out in the ATLAS experiment at the Large Hadron Collider using 2.05 fb-1 of data at a centre-of-mass energy of 7 TeV. In units of the elementary electric charge, the top quark charge…
Recent experimental results from the CDF collaboration which study the top forward-backward asymmetry have strengthened the case that new physics is playing a role in t-tbar production. Here we propose a set of measurements, built from the…
In this paper a general method to measure the longitudinal polarization of $\tau$ lepton in the process $pp \rightarrow Z^{0} \rightarrow \tau\tau$ is described. The method of optimal observable allows to distinguish between the $\tau$…
The rate and corresponding gluon jet energy distribution for the process $e^+e^- \to t\bar tg$ are sensitive to the presence of anomalous dipole-like couplings of the top to the photon and $Z$ at the production vertex. For sizeable…
We study the nature of the flavor changing neutral couplings of the top quark with the Higgs boson and the up/charm quark in the $t\bar{t}$ production at linear colliders. There are previous bounds on such tqH couplings at both, linear and…
The study of top-quark properties will be a central aspect of the physics programme of any future lepton collider. In this article, we investigate the production of top-quark pairs in the semi-leptonic decay channel in $\rm e^+e^-$…
Measuring the total cross sections of top-quark pair production and single top processes at high precision tests the predictions of the Standard Model and can bring better understanding of properties such as the top-quark mass, electroweak…
The multi-TeV energies available at LHC have opened up the possibility to measure, for the first time, various large-mass elementary particles in nuclear collisions. The current study presents the first observation of top quark--the…
A review of the recent results on measurements of top quark properties in single top quark events using data samples of proton proton collisions produced by the LHC at sqrt(s) = 7 and 8 TeV and collected by ATLAS and CMS detectors is…
The top-quark mass is one of the fundamental parameters of the Standard Model of particle physics. The latest ATLAS measurements of the top-quark mass in top quark pair final states are presented. Measurements use di-lepton, lepton+jets and…