Related papers: Is Higgsium a possibility in 2HDMs?
It is widely believed that extensions of the minimal Higgs sector is one of the promising directions for resolving many puzzles beyond the Standard Model (SM). In this work, we study the unitarity bounds on the models by extending the…
We update the allowed parameter space of the CP-violating 2HDM with Type II Yukawa couplings, that survives the current experimental and theoretical constraints on the model. For a representative set of allowed parameter points, we study…
In the Standard Model (SM), the weak gauge bosons and fermions acquire mass through the Higgs mechanism. A lower limit on the SM Higgs mass of 114.4 GeV was obtained from the direct search at LEP. Although a single Higgs doublet is…
Non-minimal composite Higgs scenarios can contain exotic Higgs states which, if getting observed at the Large Hadron Collider, will help to constrain the underlying UV structure of the strong dynamics. Doubly charged Higgs bosons are…
With the aim of exploring the Higgs sector of the Two Higgs Doublet Model (2HDM), we have chosen the exact and soft $Z_2$ symmetry breaking versions of the 2HDM with non-zero vacuum expectation values for both Higgs doublets (Mixed Model).…
Possible extensions of the Standard Model predict modifications of the Higgs couplings to gluons and to the SM top quark. The values of these two couplings can, in general, be independent. We discuss a way to measure these interactions by…
We study a system of two Higgs bound state, interacting via a real scalar Dark Matter mediating field, without imposing $Z_2$ symmetry on the DM sector of the postulated Lagrangian. The variational method in the Hamiltonian formalism of QFT…
We present a complete (non-redundant) basis of CP- and flavour-conserving six-dimensional operators in a two Higgs doublet model (2HDM). We include Z_2-violating operators as well. In such a 2HDM effective field theory (2HDMEFT), we…
We investigate how the Next-Two-Higgs Doublet Model extension (N2HDM) should look if we are to address the naturalness problem using dimensional regularization. In such a model, new Higgs states are predicted, namely: three CP-even…
In the two-Higgs-doublet model, different Higgs doublets can be viewed as components of a generic "hyperspinor". We decompose the Higgs potential of this model into irreducible representations of the SU(2) group of transformations of this…
We interpret the recent discovery of a 125 GeV Higgs-like state in the context of a two Higgs doublets model with a heavy 4th sequential generation of fermions, in which one Higgs doublet couples only to the 4th generation fermions, while…
Twin Higgs models are the prime illustration of neutral naturalness, where the new particles of the twin sector, gauge singlets of the Standard Model (SM), ameliorate the little hierarchy problem. In this work, we analyse phenomenological…
With no evidence of any exotic particle detected so far beyond the Standard Model, the new physics may lie above the presently accessible energies at colliders and, at low-energies, can be accounted for via an effective description. The…
In the two Higgs doublet model, there is the possibility that the vacuum where the universe resides in is metastable. We present the tree-level bounds on the scalar potential parameters which have to be obeyed to prevent that situation.…
We analyse the possibility that, in two Higgs doublet models, one or more of the Higgs couplings to fermions or to gauge bosons change sign, relative to the respective Higgs Standard Model couplings. Possible sign changes in the coupling of…
Within the framework of the type-II Two Higgs Doublet Model (2HDM-II) we study the production of three top quarks at the Large Hadron Collider (LHC). In the Standard Model the production cross section of three tops is low ($\approx 3$fb),…
In extended Higgs sectors that exhibit alignment without decoupling, the additional scalars are allowed to have large couplings to the Standard Model Higgs. We show that current nonresonant di-Higgs searches can be straightforwardly adapted…
We study the Higgs sector of supersymmetric models containing two Higgs doublets with a light MSSM-like CP odd Higgs, $m_A \lesssim 10$ GeV, and $\tan \beta \lesssim 2.5$. In this scenario all of the Higgses resulting from two Higgs…
One of the simplest extensions of the Standard Model (SM) consists in adding a scalar singlet. This second Higgs boson is able to solve several fundamental problems of SM. Additional scalar particles arise naturally in composite Higgs…
We study the perturbative unitarity bound given by higher dimensional bosonic operators up to dim-6 for the two-Higgs-doublet model (2HDM). They lead to new physics beyond the Standard Model. We point out that such operators can lead to a…