Related papers: Probing New Higgs-Top Interactions at the Tree-Lev…
The effect of new operators that give rise to CP-violating couplings of the type $Z t \bar{t}$ and $\gamma t \bar{t}$ are examined at future electron positron Linear Colliders (FLC). The impact of these CP-violating interactions over…
The doubly charged Higgs bosons $\Delta^{--}$ that are present in exotic Higgs representations can have lepton-number-violating couplings to $e^-e^-$. We discuss general constraints and phenomenology for the $\Delta^{--}$ and demonstrate…
A search is presented for flavour-changing neutral-current interactions involving the top quark, the Higgs boson and an up-type quark ($q=u,c$) with the ATLAS detector at the Large Hadron Collider. The analysis considers leptonic decays of…
In the framework of the $\mathcal{CP}$ conserving Two Higgs Doublet Model (2HDM), type I and II, we study the triple Higgs couplings with at least one light $h$ Higgs boson that is identified by the 125 GeV Higgs boson. We define benchmark…
The top quark flavor changing neutral current (FCNC) process is an excellent probe to search for new physics in top sector since the Standard Model expectation is extremely suppressed. We explore Higgs-mediated top quark FCNC, focusing on…
We study the LHC phenomenology of flavor changing Yukawa couplings between top quark, Higgs boson, and either an up or charm quark. Such $tuh$ or $tch$ couplings arise for instance in models in which Higgs sector is extended by the…
We investigate the feasibility of electroweak baryogenesis in a two-Higgs doublet model with lepton flavor violation. By scrutinizing the heavy Higgs boson mass spectrum, regions satisfying both strong first-order electroweak phase…
CP4 3HDM is a peculiar three-Higgs-doublet model in which a single symmetry leads to tight constraints on the scalar and Yukawa sectors. In this models, tree-level flavor-changing neutral couplings are unavoidable; however, as previously…
In the presence of CP violation, the Higgs-top coupling may have both scalar and pseudoscalar components, $\kappa_t$ and ${\tilde \kappa_t}$, which are bounded indirectly but only weakly by the present experimental constraints on the…
We explore charged-Higgs CP-violating effects in an intriguing two-Higgs doublet model which accords special status to the top quark. In this model the heaviness of the top quark originates naturally from the much larger VEV of the second…
CP4 3HDM is a curious version of the three-Higgs-doublet model built upon a CP symmetry of order 4 (dubbed CP4). When extended to fermions, CP4 leads to unusually tight correlations between the scalar and Yukawa sectors and induces…
In this contribution to the Snowmass 2021 process, we outline models with two or three Higgs doublets that address open questions of particle physics and cosmology. In particular, we show that with two additional Higgs doublets one can…
The ATLAS and CMS experiments at the LHC have reported the observation of a possible excess of events corresponding to a new particle $h$ with mass $\sim 125$ GeV that might be the long-sought Higgs boson, or something else. Decyphering the…
The non-minimal flavour violating interactions of mirror quarks and new heavy gauge bosons in the Littlest Higgs model with T-parity (LHT) give rise to naturally large CP-violating effects in the B_s system. In view of a large new CP phase…
We demonstrate that multiple-Higgs production at the LHC is the most sensitive probe of first and second-generation quark flavor in the Higgs sector. In models where new scalars couple to light quarks, gigantic di-Higgs and even sizable…
We investigate a potentially large CP violating asymmetry in the neutral Higgs boson decay into a heavy quark pair or a $W^+$--$W^-$ pair. The source of the CP nonconservation is in the Yukawa couplings of the Higgs boson which can contain…
We analyzed the triple Higgs boson self-coupling at future $e^{+}e^{-}$ colliders energies, with the reactions $e^{+}e^{-}\to b \bar b HH, t \bar t HH$. We evaluate the total cross-sections for both $b\bar bHH$ and $t\bar tHH$, and…
Proton-proton interactions resulting in final states with two photons are studied in a search for the signature of flavor-changing neutral current interactions of top quarks (t) and Higgs bosons (H). The analysis is based on data collected…
We study the sensitivity to the shape of the Higgs potential of single, double, and triple Higgs production at future $e^+e^-$ colliders. Physics beyond the Standard Model is parameterised through the inclusion of higher-dimensional…
We investigate the prospects of discovering the top quark decay into a charm quark and a Higgs boson ($t \to c h^0$) in top quark pair production at the CERN Large Hadron Collider (LHC). A general two Higgs doublet model is adopted to study…