相关论文: Vacuum (in)stability in 2HDMS vs N2HDM
The constraints from the measurements of the $B\to X_s\gamma$ decay rate on the parameter space of 3-Higgs Doublet Models (3HDMs), where all the doublets have non-zero vacuum expectation values, are studied at the next-to-leading order in…
We perform a phenomenological analysis of the observable consequences on the extended scalar sector of the SMASH (Standard Model - Axion - Seesaw - Higgs portal inflation) framework. We solve the vacuum metastability problem in a suitable…
We investigate the stability of the electroweak vacuum for two-Higgs doublet models with a supersymmetric UV completion. The supersymmetry breaking scale is taken to be of the order of the grand unification scale. We first study the case…
The usually considered vacuum of the two-Higgs-doublet model (2HDM) could be unstable if it locates at a local but not global minimum (GM) of the scalar potential. By requiring the vacuum to be a GM, we obtain an additional constraint,…
We introduce a two real scalar singlet extension of the two Higgs doublet model. We study the vacuum structure, the bounded from below conditions, the restrictions from the oblique parameters S,T and U, as well as the unitarity constraints.…
We study the vacuum stability and perturbativity conditions in the minimal type-II seesaw model. These conditions give characteristic constraints to model parameters. In the model, there is a $SU(2)_L$ triplet scalar field, which could…
The Next-to-Two-Higgs-Doublet model (N2HDM) has a rich vacuum structure where multiple electroweak (EW) breaking minima, as well as CP and electric-charge breaking minima, can coexist. These minima can be deeper than the electroweak vacuum…
We consider the small excesses around 95 GeV found in several searches for a new scalar in $\gamma \gamma$, $\tau \tau$ and $b \bar b$ final states. Instead of trying to accommodate them all, as is usually done in the literature, in the…
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…
The Two Higgs Doublet Model (2HDM) is a simple extension of the Standard Model (SM), which provides a rich and very interesting phenomenology. To remove the undesirable flavour-changing neutral currents (FCNCs), an additional $\mathcal Z_2$…
One very light neutral Higgs scalar with mass, say, below 40-50 GeV is still allowed in the non-supersymmetric 2HDM (Model II), while the remaining particles of the Higgs sector in this model have to be heavier. The possibility of testing…
The two-Higgs doublet model (2HDM) provides an excellent benchmark to study physics beyond the Standard Model (SM). In this work we discuss how the behaviour of the model at high energy scales causes it to have a scalar with properties very…
We investigate the impact of charge-breaking minima on the vacuum stability of the NMSSM. We find that, in contrast to Two-Higgs-Doublet Models like the MSSM, at both tree- and loop-level there exists global charge-breaking minima.…
Motivated by the interesting features of Two Higgs Doublet Models (2HDM) we present a 2HDM extension where the stability of dark matter, neutrino masses and the absence of flavor changing interactions are explained by promoting baryon and…
We study the simplest viable dark matter (DM) model with a real singlet scalar, vector-like singlet, and doublet fermions. The Yukawa couplings associated with the fermion sector are important in obtaining the current DM relic density…
In the standard model, the requirements of vacuum stability and the validity of perturbation theory up to the unification scale force the mass of the Higgs boson to be approximately between 130 GeV and 180 GeV. We re-examine these…
We study the possibility of a Dark Matter candidate having its origin in an extended Higgs sector which, at least partially, is related to a new strongly interacting sector. More concretely, we consider an i2HDM (i.e. a Type-I Two Higgs…
There are nowadays strong experimental constraints on supersymmetric theories from the Higgs measurements as well as from the null results in Sparticle searches. However, even the parameter spaces which are in agreement with experimental…
We investigate the recently reported $t\bar{t}$ excess by the CMS Collaboration within the framework of conventional Two-Higgs-Doublet Models (2HDMs). Considering all four types (I, II, X, and Y), we perform a comprehensive parameter space…
We study the phase diagram and the stability of the ground state for certain four-dimensional gauge-Yukawa theories whose high-energy behaviour is controlled by an interacting fixed point. We also provide analytical and numerical results…