Related papers: Study of the top reconstruction in top-partner eve…
We review recent theoretical improvements of Monte Carlo event generators for top-quark pair production and decay at the LHC based on the POWHEG method. We present an event generator that implements spin correlations and off-shell effects…
With high luminosity and energy at the ILC and clean SM backgrounds, the top-charm production at the ILC should have powerful potential to probe new physics. The littlest Higgs model with discrete symmetry named "T-parity"(LHT) is one of…
A precise measurement of the top quark mass, a fundamental parameter of the Standard Model, is among the most important goals of top quark studies at the Large Hadron Collider. Apart from the standard methods, numerous new observables and…
In the littlest Higgs model with T-parity, we study associated production of a Higgs and a single top quark at the 14 TeV LHC. We focus on the Higgs to two photons decay and the semileptonic top decay channel. By performing a fast detector…
A search for the pair production of heavy vector-like partners T and B of the top and bottom quarks has been performed by the CMS experiment at the CERN LHC using proton-proton collisions at $\sqrt{s} =$ 13 TeV. The data sample was…
The search for first top-quark pair candidate events and the related background studies using data-driven techniques are reported for about 300 inverse nb of 7 TeV proton-proton collision data delivered by the Large Hadron Collider (LHC)…
The first implementation of fragmentation in a numerical code for the computation of cross sections at next-to-next-to-leading order in QCD has recently been completed. I will present some results of the first application of this new…
We present heavy-flavor production in association with one jet in hadronic collisions matched to parton shower Monte Carlo predictions at next-to-leading order QCD with account of top-quark decays and spin correlations. We use the POWHEGBOX…
We study jet substructures of a boosted polarized top quark, which undergoes the semileptonic decay $t\to b\ell\nu$, in the perturbative QCD framework. The jet mass distribution (energy profile) is factorized into the convolution of a hard…
We survey the expected polarization of the top produced in the decay of a scalar top quark, $\tilde t \rightarrow {\tilde t}\chi_i^0, i =1-2$. The phenomenology is quite interesting, since the expected polarization depends both on the…
Top quark pair production by (polarized) gamma gamma collisions offers an interesting testing ground of the Standard Model and its extensions. In this Letter we present results for differential cross sections of top quark pair production…
A search for charged Higgs bosons decaying into a top quark and a bottom quark is presented. The data analysed correspond to 139 fb$^{-1}$ of proton-proton collisions at $\sqrt{s}$=13TeV, recorded with the ATLAS detector at the LHC. The…
We investigate the di-Higgs events through $Z_H$-pair production at the CERN Large Hadron Collider including the pure next-to-leading order (NLO) QCD correction and the $gg$-fusion contribution in the framework of the littlest Higgs model…
We investigate the prospects to observe effects of transverse polarization of top quarks in $pp,p\bar{p}\to t\bar{t}X$. QCD absorptive parts generate a polarization of top quarks and antiquarks transverse to the production plane in the…
The performance of taggers for hadronically decaying top quarks and $W$ bosons in $pp$ collisions at $\sqrt{s}$ = 13 TeV recorded by the ATLAS experiment at the Large Hadron Collider is presented. A set of techniques based on jet shape…
The study of the top quark's properties is an important part of the LHC programme. In earlier work, we have studied the rare decay $t \to b \bar b c$, using effective operators to capture the effects of physics beyond the Standard Model.…
Polarization studies for heavy quarks can lead to important tests of the Standard Model. Top quark pair production in $e^+e^-$ annihilation is considered near energy threshold. It is shown that for longitudinally polarized electrons the…
Composite Higgs models provide a natural, non-supersymmetric solution to the hierarchy problem. In these models, one or more sets of heavy top-partners are typically introduced. Some of these new quarks can be relatively light, with a mass…
A search for heavy pseudoscalar ($A$) and scalar ($H$) Higgs bosons decaying into a top quark pair ($t\bar{t}$) has been performed with 20.3 fb$^{-1}$ of proton--proton collision data collected by the ATLAS experiment at the Large Hadron…
We perform a detailed study of top-quark partner production in the ttbar plus large missing energy final-state at the LHC, presenting results for both scalar and fermionic top-quark partners in the semi-leptonic and dileptonic decay modes…