Related papers: Constraining Multi-scalars models with colliders a…
In this work, I briefly report on constraints that can be obtained on new physics models that extend the scalar sector of the Standard Model (SM) of particle physics at the LHC. I concentrate on a few simple examples which serve to…
Conservative bSM models with rich scalar sector, such as multi-Higgs-doublet models, can easily accommodate the SM-like properties of the 125 GeV scalar observed at the LHC. Possessing a variety of bSM signals, they are worth investigating…
The idea of this work is to investigate the constraints on the dark matter (DM) allowed parameter space from high scale validity (absolute stability of Higgs vacuum and perturbativity) in presence of multi particle dark sector and heavy…
We explore a fermionic dark matter model with a possible extension of Standard Model (SM) of particle physics into two Higgs doublet model. Higgs doublets couple to the singlet fermionic dark matter (FDM) through a non renormalisable…
The presence of extra scalar singlets is a feature of several motivated extensions of the Standard Model, and the mixing of such a singlet with the Higgs boson is allowed to be quite large by current experiments. In this paper we perform a…
The complex scalar dark matter (DM) candidate in the gauged two Higgs doublet model (G2HDM), stabilized by a peculiar hidden parity ($h$-parity), is studied in detail. We explore the parameter space for the DM candidate by taking into…
It is possible to ameliorate the Higgs vacuum stability problem by switching over to two Higgs doublet models (2HDM), ensuring a stable electroweak vacuum up to the Planck scale, even though the top quark mass may be on the high side.…
In this thesis, we discuss theoretical properties of various Higgs sectors, and we analyze constraints from current experimental data, and then we study collider signatures in each Higgs sector. In Part I, we focus on the phenomenology of…
There are many possibilities for new physics beyond the Standard Model that feature non-standard Higgs sectors. These may introduce new sources of CP violation, and there may be mixing between multiple Higgs bosons or other new scalar…
Weak-scale supersymmetry is a well motivated, if speculative, theory beyond the Standard Model of particle physics. It solves the thorny issue of the Higgs mass, namely: how can it be stable to quantum corrections, when they are expected to…
We give here an overview of recent developments in high energy physics and cosmology and their interconnections that relate to unification, and discuss prospects for the future. Thus there are currently three empirical data that point to…
After the Higgs discovery, the question of whether particles beyond those of the Standard Model exist is more pressing than ever. In this context, the scalar sector is particularly promising, since it lies at the core of the internal…
Models with three Higgs doublets (3HDM) are the source of much recent activity, for they are key components of many solutions to the problems of the Standard Model; from extra sources of CP violation to Dark Matter candidates. We compute…
In this study we consider an effective model by introducing two hypothetical real scalars, $H$ and $\chi$ - a dark matter candidate, where the masses of these scalars are $2 m_h < m_H < 2 m_t$ and $m_\chi \approx m_h/2$ with $m_h$ and $m_t$…
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…
Two major problems call for an extension of the Standard Model (SM): the hierarchy problem in the Higgs sector and the dark matter in the Universe. The discovery of a Higgs boson with mass of about 125 GeV was clearly the most significant…
Annihilating dark matter (DM) models based on a scalar hidden sector with Higgs portal-like couplings to the Standard Model are considered as a possible explanation for recently observed cosmic ray excesses. Two versions of the model are…
We present a systematic study of an extension of the Standard Model (SM) with two Higgs doublets and one complex singlet (2HDM+S). In order to gain analytical understanding of the parameter space, we re-parameterize the 27 parameters in the…
We have explored properties of an extension of the Inert Doublet Model by the addition of an extra non-inert scalar doublet. The model offers a possibility of CP violation in the scalar sector and a candidate for the Dark Matter. Allowed…
In this thesis, various extensions of the scalar sector have been considered comprising of different ${SU(2)_L}$ multiplets. If the extended scalar sector participates in the electroweak symmetry breaking then these extra scalars need to…