Related papers: Constraining Multi-scalars models with colliders a…
Recently, conceptually new physics beyond the Standard Model has been proposed, where a hidden conformal sector provides ``unparticle'' which couples to the Standard Model sector through higher dimensional operators in low energy effective…
In spite of the success of the Standard Model of Particle Physics, there are some theoretical predictions which are not yet fully established experimentally as well as some experimental observations which cannot be fitted within its…
In the last decades, the Standard Model (SM) of particle physics has been extensively tested and confirmed, with the announced discovery of the Higgs boson in 2012 being the last missing puzzle piece. Even though since then the search for…
We explore the dark matter sector in extensions of the Minimal Supersymmetric Standard Model (MSSM) that can provide a good fit to the PAMELA cosmic ray positron excess, while at the same time addressing the little hierarchy problem of the…
This article reviews the theoretical constraints on the scalar potential of a general extension of the Standard Model that encompasses a $SU(3)_c\times SU(3)_L\times U(1)_X$ gauge symmetry. In this respect, the boundedness-from-below is…
We consider an extension of the Standard Model involving two new scalar particles around the TeV scale: a singlet neutral scalar $\phi$, to be eventually identified as the Dark Matter candidate, plus a doubly charged $SU(2)_L$ singlet…
We investigate a beyond Standard Model (SM) featuring five new fields. Four fields encompassing three distinct spin states - scalar ($ S $), spinor ($ \psi^{1,2} $), and vector ($ V_{\mu} $) - together form the multi-component dark matter…
LHC has found hints for a Higgs particle of 125 GeV. We investigate the possibility that such a particle is a mixture of scalar and pseudoscalar states. For definiteness, we concentrate on a two Higgs doublet model with explicit CP…
We consider the classically scale invariant Higgs-dilaton model of dynamical symmetry breaking extended with an extra scalar field that plays the role of dark matter. The Higgs boson is light near a critical boundary between different…
We propose a minimal model for the cosmic coincidence problem $\Omega_{\rm DM}/\Omega_B \sim 5$ and neutrino mass in a type-II seesaw scenario. We extend the standard model of particle physics with a $\rm SU(2)$ singlet leptonic Dirac…
The great successes achieved by the Standard Model(SM) lead us to believe the existence of the Higgs particle. On the other hand, there are many evidences indicate that some unknown dark matter particle must exist in our universe. To…
With the Large Hadron Collider's Run 3 in progress, the 125 GeV Higgs boson couplings are being examined in greater detail, while searching for additional scalars. Multi-Higgs frameworks allow Higgs couplings to significantly deviate from…
In the framework of an nonuniversal $U(1)'$ extension of the standard model, we propose an scalar candidate for cold dark matter which exhibits interactions with ordinary matter through Higgs and gauge bosons. Using limits from low energy…
We investigate the predictions of a simple extension of the Standard Model where the Higgs sector is composed of one $SU(2)_L$ doublet and one real triplet. We discuss the general features of the model, including its vacuum structure,…
The recent discovery of a Higgs boson with mass of about 125 GeV, along with its striking similarity to the prediction from the Standard Model, informs and constrains many models of new physics. The Higgs mass exhausts one out of three…
We update the constraints on two-Higgs-doublet models (2HDMs) focusing on the parameter space relevant to explain the present muon $g$$-$$2$ anomaly, $\Delta a_{\mu}$, in four different types of models, type I, II, "lepton specific" (or X)…
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…
A vast literature on the theory and phenomenology of Two-Higgs-Doublet models (2HDM) exists since long. However, the present situation demands a revisit of some 2HDM properties. Now that a 125 GeV scalar resonance has been discovered at the…
The Georgi-Machacek model extends the Standard Model Higgs sector with the addition of isospin-triplet scalar fields in such a way as to preserve the custodial symmetry. The presence of higher-isospin scalars contributing to electroweak…
We consider an extension to the Standard Model (SM) with two extra real singlet scalars which interact with the SM Higgs particle. The lighter scalar is taken as the dark matter (DM) candidate. We show that the model successfully explains…