相关论文: Constraints on the septet-doublet mixing models fr…

Extending the Standard Model by adding a scalar field transforming as a septet under $SU(2)_L$ preserves the $\rho$ parameter at tree level and can satisfy experimental constraints on the electroweak parameters $S$ and $T$. This work…

We derive a general expression for Delta rho (or, equivalently, for the oblique parameter T) in the SU(2) x U(1) electroweak model with an arbitrary number of scalar SU(2) doublets, with hypercharge +-1/2, and an arbitrary number of scalar…

We study the LHC search constraints on models that extend the Standard Model (SM) with an inert, complex scalar electroweak multiplet, $\Sigma$, with isospin T=5/2 (sextet) or T=7/2 (octet) and identical hypercharge to the SM Higgs doublet.…

We calculate the oblique electroweak corrections and confront them with the experiments in a composite Higgs version of the standard model. A vector-like weak doublet and a singlet fermion are added to the standard model without elementary…

The single Higgs doublet in the standard model (SM) may be the simplest way of introducing electroweak symmetry breaking, but SM extensions with more scalar doublets are not excluded. A special case of the two Higgs doublet models is the…

In this work, we consider an extension of the Standard Model (SM) with an inert Higgs doublet and a real scalar singlet, in order to address problems around the origin of dark matter (DM). In this model, the lightest among the CP-odd and…

Imposing the theoretical constraints from vacuum stability, unitarity and perturbativity as well as the experimental constraints from the electroweak precision data, flavor observables and the non-observation of additional Higgs at…

The scalar septet model extends the Standard Model Higgs sector by an isospin septet with hypercharge chosen to preserve $\rho \equiv M_W^2/M_Z^2 \cos^2\theta_W = 1$. In this paper we constrain the model at high septet masses using…

We consider the addition of a single $SU(2)$ multiplet of complex scalar fields to the Standard Model (SM). We explicitly consider the various possible values of the weak isospin $J$ of that multiplet, up to and including $J = 7/2$. We…

Constraints on the two Higgs doublet model are presented, assuming a top mass of 174 $\pm$ 17 GeV. We concentrate primarily on the ``type II'' model, where up--type quarks receive their mass from one Higgs doublet, and down--type quarks…

We propose a simple extension of the Standard Model (SM) which has a viable dark matter (DM) candidate, as well as can explain the generation of tiny neutrino masses. The DM is an electroweak (EW) singlet scalar $S$, odd under an imposed…

The 2HDM+S is the singlet extension of the Two-Higgs-Doublets Model (2HDM). The singlet field and its mixing with the 2HDM Higgs sector lead to new contributions to the electroweak precision observables, in particular, the oblique…

We study the stability constraints on the parameter space of a triplet extension of MSSM. Existence of unbounded from below directions in the potential can spoil successful Electroweak (EW) symmetry breaking by making the corresponding…

We extend the so-called singlet doublet dark matter model, where the dark matter is an admixture of a Standard Model singlet and a pair of electroweak doublet fermions, by a singlet scalar field. The new portal coupling of it with the dark…

Models with an extended scalar electroweak sector are well motivated. Such models could accommodate a dark matter candidate if there is an additional scalar representation with a vanishing vacuum expectation value and, in addition, there…

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)…

In this paper we investigate the next-to-minimal composite Higgs model with a SO(6)/SO(5) coset, whose pNGB sector includes a Standard Model singlet in addition to the usual Higgs doublet. The fermions are embedded in the representation 6…

We discuss the parameter space of the Inert Doublet Model, a two Higgs doublet model with a dark matter candidate. An extensive set of theoretical and experimental constraints on this model is considered, where both collider as well as…

We study the extension of the Standard Model (SM) by introducing a scalar multiplet with arbitrary isospin $J$ and hypercharge $Y$. We explicitly consider various possible values of the weak isospin $J$, up to and including $J=7/2$. The…

The Inert Doublet Model relies on a discrete symmetry to prevent couplings of the new scalars to Standard Model fermions. This stabilizes the lightest inert state, which can then contribute to the observed dark matter density. In the…