Related papers: SM scalar and extra singlet(s)
An extension of the Standard Model with an additional Higgs singlet is analyzed. Bounds on singlet admixture in 125 GeV h boson from electroweak radiative corrections and data on h production and decays are obtained. Possibility of double h…
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…
In a class of new physics models, new physics sector is completely or partly hidden, namely, singlet under the Standard Model (SM) gauge group. Hidden fields included in such new physics models communicate with the Standard Model sector…
We consider present constraints on Two Higgs Doublet Models, both from the LHC at Run 1 and from other sources in order to explore the possibility of constraining a neutral scalar or pseudo-scalar particle lighter than the 125 GeV Higgs…
The threshold dependence and angular correlations of Higgs-strahlung in e+e- collisions can be used to demonstrate the spinless nature of the Standard Model Higgs boson. This method, and its possible extention to heavy neutral MSSM Higgs…
We investigate the signatures of the recently proposed Higgsless models at future colliders. We focus on tests of the mechanism of partial unitarity restoration in the longitudinal vector boson scattering, which do not depend on any…
We consider a simple extension of the Standard Model by the addition of N real scalar gauge singlets $\vp$ that are candidates for Dark Matter. By collecting theoretical and experimental constraints we determine the space of allowed…
The Higgs potential of the standard model with an additional real Higgs singlet is studied in order to examine if it may allow the strongly first order electroweak phase transition. It is found that there are parameter values for which this…
The present experimental and theoretical knowledge of the physics of electroweak symmetry breaking is reviewed. Data still favor a light Higgs boson, of a kind that can be comfortably accommodated in the Standard Model or in its Minimal…
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) is the addition of a scalar gauge singlet, S. If S is not forbidden by a symmetry from mixing with the Standard Model Higgs boson, the mixing will generate non-SM rates for Higgs…
The interplay of prospective experimental information from both the Large Hadron Collider (LHC) and the Linear Collider (LC) in the investigation of the MSSM Higgs sector is analyzed in the SPS~1a and SPS 1b benchmark scenarios. Combining…
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…
Extensions of the Standard Model Higgs sector involving weak isotriplet scalars are not only benchmark candidates to reconcile observed anomalies of the recently discovered Higgs-like particle, but also exhibit a vast parameter space, for…
One of the simplest models of dark matter is that where a scalar singlet field S comprises some or all of the dark matter, and interacts with the standard model through an HHSS coupling to the Higgs boson. We update the present limits on…
If the Standard Model of particle interactions is extended to include a second scalar doublet $[H^{+},(H^{0}+iA^{0})/\sqrt{2}]$, which is odd under an unbroken Z_{2} discrete symmetry, it may be called the $dark$ scalar doublet, because its…
We consider general fermi-phobic scenarios in which excess events in diphoton or WW/ZZ resonances may be seen at LHC. These Higgs like signals do not necessarily suggest that the new resonance is a particle with Yukawa couplings nor do we…
In a recent paper we showed that the Minimal R-symmetric Supersymmetric Standard Model (MRSSM) can accommodate the observed 125 GeV Higgs boson as the lightest scalar of the model in agreement with electroweak precision observables, in…
We investigate the influence of scalar gauge singlets on Higgs signals at a linear collider. These lead to a large invisible decay width of the Higgs. We find that for high luminosities ($500-1000 fb^{-1}$) one can essentially cover the…
A summary of the sensitivity of the ATLAS and CMS experiments at the LHC to discover a Standard Model Higgs boson is presented. Some prospects for Minimal Supersymmetric Standard Model Higgs searches at LHC are also included.