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The latest top quark studies in proton-proton collisions at a centre-of-mass energy of 7 and 8 TeV with the ATLAS detector are reported. We present recent results on the top pair production inclusive cross-sections, top pair production differential cross-section in the resolved and boosted regimes, single top-quark production cross-sections measured in the t-channel, s-channel and W-boson associated processes, as well as the determination of the CKM matrix element $\left|V_{tb}\right|$. The results are compared with theoretical expectations. Latest ATLAS results on top properties will be also shown in terms of direct and pole mass, spin correlations and charge asymmetry.

Top quarks are copiously produced at the LHC. The measurements are in stage for precision. A review on top-quark properties measured by the ATLAS, CMS and LHCb collaborations is presented, including the mass of the top quark, coupling, production cross sections and decay properties.

We discuss the polarization effects in top quark decays and their QCD radiative corrections. As an example, we give NLO QCD results to polarized top decay into a charged Higgs to highlight the details of our calculations.

We consider a dynamical scenario improving the naturalness of the standard model, in which the Higgs field has a large anomalous dimension through conformally invariant coupling with an extra gauge sector above TeV scale. The large top Yukawa coupling is generated effectively through mixing top quarks and the fermions of the extra gauge sector. We present an explicit model consistent with the Electro-Weak precision tests.

The Fermilab Tevatron is currently the only collider capable of producing and studying top quarks. The dominant mechanism for top quark production at the Tevatron is production via the strong interaction. The precise measurement of the cross section of this process is a test of the QCD prediction. In Run II of the Tevatron it should be possible to achieve an experimental error on this cross section which is comparable or better than the current theoretical precision. This paper presents the basic event selection criteria for events at the Tevatron and the latest measurements of the cross section.

Measurements of the top quark mass from Run II of the Tevatron using integrated luminosities from 370 pb^-1 to 1030 pb^-1 are presented. Results from the CDF and DØ experiments in different channels are combined resulting in m_t = 171.4 ± 2.1 GeV/c². This corresponds to a relative uncertainty of 1.2%.

With its discovery in 1995 by the CDF and DØ collaborations the top quark completed the set of quarks expected by the Standard Model. It is predicted to have the same quantum numbers and couplings as the other up-type quarks. Albeit, only very few of these properties have been verified so far. This article summarises the existing measurements of top quark properties in the pair production mode.

The top quark is the heaviest and the least studied quark of the Standard Model (SM). At the LHC several millions of top quarks will be produced every year through pair and single top production. Precision tests of the SM performed by the ATLAS and CMS collaborations (top mass, cross sections, top spin correlations and W polarization) are reviewed together with the studies of the sensitivity to new physics beyond the SM (anomalous couplings and FCNC decays) using and single top events.

We introduce a deconstructed model that incorporates both Higgsless and top-color mechanisms. The model alleviates the typical tension in Higgsless models between obtaining the correct top quark mass and keeping Δ_ρ small. It does so by singling out the top quark mass generation as arising from a Yukawa coupling to an effective top-Higgs which develops a small vacuum expectation value, while electroweak symmetry breaking results largely from a Higgsless mechanism. As a result, the heavy partners of the SM fermions can be light enough to be seen at the LHC.

One of the main goal of the Large Hadron Collider (LHC) experiments at CERN in Switzerland is to aim to solve the “origin of the mass” by discovering the Higgs boson and understanding the interaction of the Higgs boson with the elementary particles. The ATLAS, which is one of the LHC experiments has taken about 5 fb⁻¹ of physics quality data and published several results with regard to the “origin of the mass” since March 2010. This presentation focuses on the latest results of the heaviest elementary particle, namely, top quark physics and the Higgs boson searches from ATLAS.

This paper summarises the latest experimental results on top quark physics by the ATLAS Collaboration using LHC pp collisions data corresponding to an integrated luminosity of 4.7 fb⁻¹ at and 20.3 fb⁻¹ at . Results presented here cover different aspects of the top quark studies including searches for physics beyond the Standard Model.