Related papers: Effects of a Real Singlet Scalar on Veltman Condit…
In a number of Higgs-portal models, an $SU(2)$ isospin-singlet scalar boson generically appears at the electroweak scale and can mix with the Standard Model (SM) Higgs boson with a mixing angle $\alpha$. This singlet scalar boson can have…
The newly discovered resonance at 125 GeV has properties consistent with the Standard Model (SM) Higgs particle, although some production and/or decay channels currently exhibit O(1) deviations. We consider scenarios with a new scalar…
We study a simple extension of the Standard Model with a vector-like down-type quark $D$ and a neutral singlet scalar ${\cal S}=S_R,\Phi$. The scalar is considered in two forms, a real field $S_R=S_R^\dagger$ and a complex field…
We analyze one-loop vacuum stability, perturbativity, and phenomenological constraints on a complex singlet extension of the Standard Model (SM) scalar sector containing a scalar dark matter candidate. We study vacuum stability…
Implications of additional fundamental scalar fields are regarded as among the most important avenues to explore after the experimental discovery of the standard model Higgs, particularly when there already exist cogent arguments in favor…
A real singlet scalar, connected to the Standard Model sector through a portal with the Higgs boson, is one of the simplest and most popular models for dark matter (DM). However, the experimental advances in direct and indirect DM searches,…
We adopt a bottom-up Effective Field Theory (EFT) approach to derive a model-independent Veltman condition to cancel the quadratic divergences in the Higgs mass. We show using the equivalence theorem that all deviations in the Higgs…
We consider the Higgs sector in an extension of the MSSM involving an extra U(1)' gauge symmetry and SM singlet U(1)' charged scalars, in which the effective $\mu$ parameter is decoupled from the Z' mass. There are large mixings between…
We investigate a supersymmetric extension of the Minimal Supersymmetric Standard Model (MSSM), called the TNMSSM, containing a $SU(2)$ Higgs triplet $(\hat{T})$ of $Y=0$ hypercharge and a singlet superfields $(\hat{S})$ in the corresponding…
In this paper we explore models in which we add a singlet scalar Higgs to the Standard Model. All of these models explain the origin of the mass hierarchy amongst the fermion masses and mixing angles. We discuss 24 different variations on…
We show that the addition of real scalars (gauge singlets) to the Standard Model can both ameliorate the little hierarchy problem and provide realistic Dark Matter candidates. To this end, the coupling of the new scalars to the standard…
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…
The minimal extension of the scalar sector of the standard model contains an additional real scalar field with no gauge quantum numbers. Such a field does not couple to the quarks and leptons directly but rather through its mixing with the…
Models of Gauge-Higgs unification in extra dimensions offer a very elegant playground where one can study electroweak symmetry breaking. The nicest feature is that gauge symmetry itself protects the Higgs potential from divergences, thus…
In the general Higgs portal like models, the extra neutral scalar, $S$, can mix with the Standard Model (SM) Higgs boson, $H$. We perform an exploratory study focusing on the direct search for such a light singlet $S$ at the Large Hadron…
We analyze the effects of introducing vector fermions in the Higgs Triplet Model. In this scenario, the model contains, in addition to the Standard Model particle content, one triplet Higgs representation, and a variety of vector-like…
We study the phenomenology of gauge singlet extensions of the Standard Model scalar sector and their implications for the electroweak phase transition. We determine the conditions on the scalar potential parameters that lead to a strong…
We explore new physics scenarios which are optimally probed through precision Higgs measurements rather than direct collider searches. Such theories consist of additional electroweak charged or singlet states which couple directly to or mix…
We argue that adding gauge-singlet real scalars to the Standard Model can both ameliorate the little hierarchy problem and provide a realistic source of Dark Matter. Masses of the scalars should be in the 1-3 TeV range, while the lowest…
The aim of this study is to investigate the quadratic divergences using dimensional regularization within the context of the standard model extended by two real scalar singlets (TRSM). This extension provides three neutral scalar fields…