Related papers: From the Higgs to the top: Couplings and Rare Deca…
Testing the properties of the Higgs particle discovered at the LHC and searching for new physics signals, are some of the most important tasks of Particle Physics today. Current measurements of the Higgs couplings to fermions and gauge…
The rare decay modes Higgs $\rightarrow$ four light fermions, and Higgs $\rightarrow$ single top-quark + three light fermions for $m_t<M_H<2m_t$, are presented, and phenomenologically interpreted. The angular correlation between fermion…
The Large Hadron Collider (LHC) has measured the Higgs boson couplings with the heavier particles of the Standard Model (SM), and they seem to lay on a single line as function of the particle mass, as predicted in the SM. However a complete…
As the Higgs boson properties settle, the constraints on the Standard Model extensions tighten. We consider all possible new fermions that can couple to the Higgs, inspecting sets of up to four chiral multiplets. We confront them with…
There is a surprising connection between the top quark and Higgs alignment in Gildener-Weinberg multi-Higgs doublet models. Were it not for the top quark and its large mass, the coupling of the 125 GeV Higgs boson $H$ to gauge bosons and…
We discuss the impact and potential discovery of physics beyond the Standard Model, coupling to the Higgs sector, at the LHC. Using a model-independent effective Lagrangian approach, pure Higgs and Higgs-gauge operators are analyzed, and…
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…
The standard-model Higgs boson couples to quarks through a parity-even scalar $Hq{\bar q}$ coupling. We show that the rare Higgs decay $H\to VZ$, where $V$ is a vector quarkonium state such as $J/\psi$ ($c{\bar c}$) or $\Upsilon(1S)$…
After more than a decade from its discovery, the Higgs boson remains at the centre of the particle physics programme. While its couplings to vector bosons and third-generation fermions have been measured with impressive precision, the…
Standard-Model Higgs bosons are dominantly produced via the gluon-fusion mechanism $gg \to H$ at the LHC, i.e. in a loop-mediated process with top loops providing the dominant contribution. For the measured Higgs boson mass of $\sim 125$…
Performing a fit to all publicly available data, we analyze the extent to which the latest results from the LHC and Tevatron constrain the couplings of the Higgs boson-like state at ~ 125 GeV. To this end we assume that only Standard Model…
Based on recent LHC Higgs analyses and in anticipation of future results we revisit theories where Higgs bosons can couple to weak gauge bosons with enhanced strength relative to the Standard Model value. Specifically, we look at the…
A variant of the conventional Higgs model is proposed which separates the physics of the Higgs decay modes from the problem of fermion mass generation. The lowest mass Higgs boson has no significant bottom decay mode but a charm and up…
Exclusive rare Higgs decays into lepton pair plus one light hadron, such as $h\to \rho^0(\omega)\ell\bar{\ell}$, $h\to \pi^0\ell\bar{\ell}$, $h\to \pi^+ (K^+)\ell^-\bar{\nu}_\ell$, and $h\to \rho^+(K^{*+})\ell^-\bar{\nu}_\ell$, have been…
It is pointed out that in a wide class of models reminiscent of type-II Two-Higgs-Doublet Models (2HDM) the signal of the Higgs produced in association with a top-antitop quark pair ($tth$) and decaying into gauge bosons can be…
We show how LHC Higgs boson production and decay data can be used to extract gauge and fermion couplings of Higgs bosons. We show that very mild theoretical assumptions, which are valid in general multi-Higgs doublet models, are sufficient…
We study new physics effects on the couplings of weak gauge bosons with the lightest CP-even Higgs boson ($h$), $hZZ$, and the tri-linear coupling of the lightest Higgs boson, $hhh$, at the one loop order, as predicted by the two Higgs…
We discuss the phenomenology of many Higgs doublet model - the model where each Higgs isodoublet couples with each own quark and lepton with relatively big Yukawa coupling constants. Namely, we discuss the discovery potential of the Higgs…
We investigate the determination of Higgs boson couplings to gauge bosons and fermions at the LHC from data on Higgs boson production and decay. We demonstrate that very mild theoretical assumptions, which are valid in general multi-Higgs…
We review possible properties of Higgs bosons in the NMSSM, which allow to discriminate this model from the MSSM: masses of mostly Standard-Model-like Higgs bosons at or above 140 GeV, or enhanced branching fractions into two photons, or…