Related papers: Constraining $qqtt$ operators from four-top produc…
Twenty years past its discovery, the top quark continues attracting great interest as experiments keep unveiling its properties. An overview of the latest measurements in the domain of top quark production, performed by the ATLAS and CMS…
The Higgs self-couplings remain only weakly constrained by current Large Hadron Collider (LHC) measurements, leaving ample room for physics beyond the Standard Model that could modify the structure of the Higgs potential. Multi-Higgs…
We discuss the results for the four-top quark production process at the LHC at NLO accuracy in perturbative QCD for the $3\ell$ decay channel. The QCD corrections are applied in both the production and the decay stages of the four top…
In this paper, we investigate the prospects of measuring the strong and weak dipole moments of the top quark at the Large Hadron Collider (LHC). Measurements of these couplings provide an excellent opportunity to probe new physics…
The detection of production of a pair of Higgs bosons before the end of LHC operation would be clear evidence of New Physics (NP). As searches for non-resonant production of Higgs pairs are being designed it is of particular importance to…
It was reported that the NNLO correction to the total cross section near the ttbar threshold in e+e- collisions is as large as the NLO correction to it. In the thesis, we improve the convergence of the perturbative series of the total cross…
An overview of recent measurements of differential top quark pair production cross sections performed by the CMS experiment at the LHC is presented. Measurements at different proton-proton center-of-mass energies are available using the…
In the absence of a concrete discovery of new physics at the LHC, global analyses of the standard model effective field theory (SMEFT) are important to find and describe the impact of new physics beyond the energy reach of the LHC. Among…
We investigate top quark pair production near the threshold where the pair invariant mass $M_{t\bar{t}}$ approaches $2m_t$, which provides sensitive observables to extract the top quark mass $m_t$. Using the effective field theory methods,…
We investigate the prospects to systematically improve generic effective field theory-based searches for new physics in the top sector during LHC run 2 as well as the high luminosity phase. In particular, we assess the benefits of high…
The role of the top quark in completing the Standard Model quark sector is reviewed, along with a discussion of production, decay, and theoretical restrictions on the top quark properties. Particular attention is paid to the top quark as a…
We investigate flavour violating four Fermi Standard Model Effective Field Theory (SMEFT) operators of dimension-six that can be probed via $tc ~(\bar{t}c+t\bar{c})$ production at the multi-TeV muon collider. We study different FCNC and…
The polarisation of top quarks produced in high energy processes can be a very sensitive probe of physics beyond the Standard Model. The kinematical distributions of the decay products of the top quark can provide clean information on the…
The large top-quark samples collected with the ATLAS experiment at the LHC have yielded measurements of the inclusive \ttbar production cross section of unprecedented precision and differential measurements in new kinematic regimes.They…
Triggered by the observation of four top-quark production at the LHC by the ATLAS and CMS collaboration we report on the calculation of the next-to-leading order QCD corrections to the Standard Model process $pp \to t\bar{t}t\bar{t}$ in the…
We present results of phenomenological studies for top-quark pair production at the LHC at the center of mass energy $\sqrt{S} = 7$ TeV. The transverse momentum and rapidity distributions for final-state top quarks are calculated in…
By questioning the applicability of the static approximation of the Colour-Singlet Model, we have seen that the production amplitude receives contributions from two different cuts. The first one in its static limit gives the colour-singlet…
We examine new aspects of leptoquark (LQ) phenomenology using effective field theory (EFT). We construct a complete set of leading effective operators involving SU(2) singlets scalar LQ and the SM fields up to dimension six. We show that,…
We study single top quark production in association with a $WZ$ pair at the LHC in the context of the Standard Model (SM) and the Standard Model Effective Field Theory (SMEFT). A significant advantage of $tWZ$ compared to other EW top…
We calculate the one- and two-loop matching corrections in the Standard Model effective field theory (SMEFT) that impact electroweak precision measurements and flavour physics observables, focusing on the contributions of third-generation…