Related papers: Top couplings and top partners
We discuss possibilities to measure the tt-gamma and ttZ couplings at hadron and lepton colliders. We also briefly describe how these measurements can be used to constrain the parameter space of models of new physics, in particular Little…
At the LHC associated top quark and Higgs boson production with a Higgs decay to bottom quarks has long been a heavily disputed search channel. Recently, it has been found to not be viable. We show how it can be observed by tagging massive…
The study of the properties of the observed Higgs boson is one of the main research activities in High Energy Physics. Although the couplings of the Higgs to the weak gauge bosons and third generation quark and leptons have been studied in…
We consider models with multiple Higgs scalar gauge singlets and the resulting restrictions on the parameters from precision electroweak measurements. In these models, the scalar singlets mix with the SU(2) Higgs doublet, potentially…
A large set of models beyond the Standard Model of particle physics suggest that the top quark plays a special role in fundamental interactions. At the same time some of these models predict that a particle responsible for dark matter is…
We complement the analysis of the anomalous top-Higgs coupling effects on the secondary lepton distributions in the associated production of the top-quark pair and Higgs boson in proton-proton collisions at the LHC of the former work by one…
Top quarks produced in pairs are predicted to experience spin correlations. Due to the large ttbar statistics expected for the LHC, it should be possible to search for new physics effects in angular variables sensitive to these…
If the gauge fields of the Standard Model propagate in TeV-size extra dimensions, they rapidly become strongly coupled and can form scalar bound states of quarks and leptons. If the quarks and leptons of the third generation propagate in 6…
In this paper we investigate a natural extension of the Standard Model that involves varying coupling constants. This is a general expectation in any fundamental theory such as string theory, and there are good reasons for why new physics…
In this paper we investigate the determination of the coupling structure of a Higgs boson at the LHC using angular correlations in the decay chain H -> ZZ -> 4l. We consider the most general couplings of a scalar to spin 1 particles and…
We describe a deconstructed Higgsless model in which electroweak symmetry breaking results largely from a Higgsless mechanism while the top quark mass is generated by a topcolor mechanism. The top quark mass arises from a Yukawa coupling to…
In supersymmetric models, a correlation exists between the structure of the Higgs sector quartic potential and the coupling of the lightest CP-even Higgs to fermions and gauge bosons. We exploit this connection to relate the observed value…
The measurement of quantum entanglement can provide a new and most sensitive probe to physics beyond the Standard Model. We use the concurrence of the top-quark pair spin states produced at colliders to constrain the magnetic dipole term in…
As LHC's Run3 unfolds, we peer deeper into the couplings of the 125GeV Higgs ($h_{125}$) and also test for extra scalars. Even before such extra scalars are found, one can probe them by using the fact that theories with multiple Higgs…
In this paper we investigate methods to study the $t\bar{t}$ Higgs coupling. The spin and CP properties of a Higgs boson are analysed in a model-independent way in its associated production with a $t\bar{t}$ pair in high-energy $e^+e^-$…
Focusing attention on top-quark pair production and its decay processes at the LHC, non-standard top-quark couplings are studied based on the effective Lagrangian constructed with SU(3)X SU(2)X U(1) invariant dimension-6 operators. The…
We give the upper bounds on the masses of the lightest and second lightest CP even Higgs bosons in the NMSSM, the MSSM extended by a gauge singlet. The dominant two loop corrections are included. Since the coupling R of the lightest Higgs…
For a new family-nonuniversal gauge interaction to be accessible at the LHC it will most likely couple preferentially to the third family. By coupling to all members of the third family the production of a new gauge boson (the $X$ with…
Three aspects of supersymmetric theories are discussed: electroweak symmetry breaking, the issues of flavor, and gauge unification. The heavy top quark plays an important, sometimes dominant, role in each case. Additional symmetries lead to…
The Standard Model Higgs boson may be mixed with another scalar that does not couple to fermions. The electroweak quantum numbers of such an additional scalar can be determined by measuring the quartic Higgs-Higgs-vector-vector couplings,…