Related papers: Constraining $qqtt$ operators from four-top produc…
Recently, experimental collaborations have reported $\mathcal{O}(10)$ upper limits on the signal strength of four-top production at the LHC, which already leads to competitive constraints on certain type of top-quark operators. On the other…
Numerical simulations of processes of three and four top quark hadroproduction are carried out in the SMEFT model framework. The simulated data are used to derive expected theoretical constraints on Wilson coefficients of relevant SMEFT…
Multi-top quark production is a staple program at the LHC. Single-top and $t\bar t$ productions are studied extensively, while current efforts are zooming in on four-top search, where the Standard Model (SM) cross section is at ${\cal…
We study the effects of four-heavy-quark operators in the production of top quarks in the framework of the Standard Model Effective Field Theory (SMEFT) at the LHC. In particular, we compute for the first time the total contribution of the…
Effective field theory (EFT) approaches are widely used at the LHC, such that it is important to study their validity, and ease of matching to specific new physics models. In this paper, we consider an extension of the SM in which a top…
The production of four top quarks is a rare process in the Standard Model that provides unique opportunities and sensitivity to Standard Model observables including potential enhancement from many popular new physics extensions. This…
In this paper, we examine the sensitivity of the three-top quark production at the LHC to the top quark flavor-changing neutral currents (FCNC) as well as the sensitivity of the four-top production to the strong and weak dipole moments of…
We establish constraints on the dimension-six four-heavy-quark operators in the Standard Model Effective Field Theory (SMEFT) by synthesising LHC measurements of top-quark and single-Higgs production with electroweak precision observables.…
We study single top quark production in association with a lepton-neutrino pair at the LHC within the framework of the Standard Model Effective Field Theory (SMEFT). We focus on relevant two-quark-two-lepton operators ($O^{3}_{lq}$,…
We present a study of four top quark production at the LHC in the Standard Model Effective Field Theory (SMEFT). The analysis is performed at the tree-level, including all terms from the mixed QCD-EW-coupling cross-section expansion and all…
We study top-antitop pair production in proton-proton collisions within the Standard Model Effective Field Theory (SMEFT) at dimension 6. We focus on the top chromomagnetic operator $C_{tG}$ together with the four-quark operators relevant…
New physics can manifest itself by an appreciable increase of the decay rate of top quarks in rare flavour-changing final states. Exploiting the large top quark production rate at the LHC, we bound four-fermion operators contributing to…
In this paper, we study the triple top quark production at the future high-energy proton-proton colliders to probe the four-fermion interactions involving three top quarks. We employ the Standard Model Effective Field Theory (SMEFT) to find…
Many theories, from Supersymmetry to models of Strong Electroweak Symmetry Breaking, look at the production of four top quarks as an interesting channel to evidentiate signals of new physics beyond the Standard Model. The production of…
Interference effects in effective field theory (EFT) analyses can significantly distort sensitivity expectations, leaving subtle yet distinct signatures in the reconstruction of final states crucial for limit setting around Standard Model…
We study the sensitivity to physics beyond the standard model of precise top-quark pair production measurements at future lepton colliders. A global effective-field-theory approach is employed, including all dimension-six operators of the…
The charge asymmetry in top quark production at hadron colliders is sensitive to beyond-the-Standard-Model four-fermion interactions. In this study we compare the sensitivity of cross-section and charge asymmetry measurements to effective…
We use an effective field theory (EFT) which includes all possible gluon-Higgs dimension-5 and dimension-7 operators to study Higgs boson plus jet production in next-to-leading order QCD. The EFT sheds light on the effect of a finite top…
This paper presents the observation of four-top-quark ($t\bar{t}t\bar{t}$) production in proton-proton collisions at the LHC. The analysis is performed using an integrated luminosity of 140 fb$^{-1}$ at a centre-of-mass energy of 13 TeV…
The next-to-leading order analysis for the cross section for hadroproduction of top quark pairs close to threshold is presented. Within the framework of non-relativistic QCD a significant enhancement compared to fixed order perturbation…