Related papers: Tree-level metastability bounds for the most gener…
We refine and update the metastability constraint on the Standard Model top and Higgs masses, by analytically including gravitational corrections to the vacuum decay rate. Present best-fit ranges of the top and Higgs masses mostly lie in…
We consider a general two-Higgs-doublet model with CP violation in the scalar sector, that leads, at the one-loop level of the perturbation expansion, to CP-violation in the process $e^+e^- \to t\bar{t} \to l^\pm ...$ and $e^+e^- \to…
We study how general two Higgs doublet models can be constrained by considering their properties under renormalization group evolution of the Yukawa couplings. We take into account both the appearance of a Landau pole as well as…
We study quark flavor violating interactions mediated by the Higgs boson $h$. We consider observables involving a third generation quark, of both the up and the down quark sectors, like $h\rightarrow bs$ and $t\rightarrow ch$. Using an…
In the {\sl type II seesaw} model, if spontaneous violation of the lepton number conservation prevails over that of explicit violation, a rich Higgs sector phenomenology is expected to arise with light scalar states having mixed…
We analyse the constraints and some of the phenomenological implications of a class of two Higgs doublet models where there are flavour-changing neutral currents (FCNC) at tree level but the potentially dangerous FCNC couplings are…
We investigate CP violating 2 Higgs doublet models as an effective theory emerging from models with an $SU(3)_L \otimes U(1)_X$ gauge symmetry. Because of the extension of the electroweak symmetry, a characteristic structure of Yukawa…
New sources of CP violation are necessary to solve the problem of the baryon asymmetry of the Universe. Extending Higgs sector is one way to introduce such new CP violating phases, and studying observables resulting from the CP violation is…
The decay $K_L\rightarrow \pi^o\nu\overline{\nu}$ is an excellent probe of the nature of CP violation. It is almost entirely CP-violating, and hadronic uncertainties are negligible. Experiments which hope to detect the decay are currently…
We perform a systematic analysis of an extension of the Standard Model that includes a complex singlet scalar field and is scale invariant at the tree level. We call such a model the Minimal Scale Invariant extension of the Standard Model…
We perform a comprehensive study of The Higgs potential of the two Higgs doublet model extended by a real triplet scalar field $\Delta$. This model, dubbed $2\mathcal{HDM+T}$, has a rich Higgs spectrum consisting of three CP-even Higgs…
We constructed a four-Higgs-doublet model (4HDM) invariant under D_5 symmetry and investigated its complete neutral vacuum structure in detail. Assuming explicit CP conservation in the scalar potential, we examined whether CP symmetry can…
We confront the Two-Higgs-Doublet Model with a variety of experimental constraints as well as theoretical consistency conditions. The most constraining data are the \bar B\to X_s\gamma decay rate (at low values of M_{H^\pm}), and \Delta\rho…
We study the high-scale validity of a Type-X two Higgs doublet scenario which provides an explanation of the observed value of muon $(g-2)$. This region admits of a pseudoscalar physical state, which is well below the observed 125-GeV…
Motivated by cosmological applications like electroweak baryogenesis, we develop a field theoretic approach to the computation of particle currents on a space-time dependent and CP-violating Higgs background. We consider the Standard Model…
Discovering CP-violating effects in the Higgs sector would constitute an indisputable sign of physics beyond the Standard Model. We derive constraints on the CP-violating Higgs-boson couplings to top and bottom quarks as well as to tau…
We investigate the standard model (SM) with the extension of a charged scalar having fractional electromagnetic charge of $-1/3$ unit and with lepton and baryon number violating couplings at tree level. Without directly taking part in the…
The Two-Higgs Doublet Model (2HDM) is a well-motivated theoretical framework that provides additional sources of CP Violation (CPV) beyond the Standard Model (SM). After studying the vacuum topology of a general (convex) 2HDM potential, we…
The current experimentally measured parameters of the Standard Model (SM) suggest that our Universe lies in a metastable electroweak vacuum, where the Higgs field is prone to vacuum decay to a lower state with catastrophic consequences. Our…
Spontaneous CP--violation in the minimal supersymmetric standard model with a gauge singlet and a cubic superpotential is examined. Although the tree--level Higgs potential conserves CP, it is shown that with the inclusion of the one--loop…