Related papers: Vector Higgs-Portal Dark Matter: How UV Completion…
The Higgs portal of the Standard Model provides the opportunity for coupling to a very light scalar field $\phi$ via the super-renormalizable operator $\phi(H^\dagger H)$. This allows for the existence of a very light scalar dark matter…
We revisit the simplest model of Higgs portal fermionic dark matter. The dark matter in this scenario is thermally produced in the early universe due to the interactions with the Higgs boson which is described by a non-renormalisable…
An extended Higgs sector may allow for new scalar particles well below the weak scale. In this work, we present a detailed study of a light scalar $S$ with enhanced coupling to leptons, which could be responsible for the existing…
In the Kinetic Mixing (KM) portal scenario, the interaction of dark matter (DM) with the particles of the Standard Model (SM) is generated by diagrams connecting the familiar photon with its dark sector analog, the dark photon (DP), via…
In a scenario of Higgs portal dark matter, Higgs exchange processes are essential for both dark matter annihilation in the early Universe and direct search experiments. The CDMS II collaboration has recently released their final results on…
We investigate dark matter phenomenology and Higgs inflation in a dark $U(1)_D$-extended model. The model features two dark matter candidates, a dark fermion and a dark vector boson. When the fermion dark matter $\psi$ is heavier than the…
In this thesis, we investigate various possibilities of Weakly Interacting Massive Particle (WIMP) dark matter (DM) and their implications. These possibilities are important because they challenge the viability of WIMP DM in light of tight…
We consider an extension of the Standard Model involving two new scalar particles around the TeV scale: a singlet neutral scalar $\phi$, to be eventually identified as the Dark Matter candidate, plus a doubly charged $SU(2)_L$ singlet…
We study the experimental constraints on dark sector CP violation that enters the visible sector through a Higgs portal coupling $H^{\dagger} H Z^{\prime}_{\mu\nu} \widetilde Z^{\prime \mu\nu}$, where the $Z^{\prime}$ is from a new U(1)…
After the observation in 2012 of a new scalar particle closely resembling the Higgs boson of the Standard Model of particle physics, there is a general consensus that there must be Physics Beyond the Standard Model, with present experiments…
We examine the interplay between Higgs mediation of dark matter annihilation and scattering on one hand, and the invisible Higgs decay width on the other, in a generic class of models utilizing the Higgs portal. We find that, while the…
We study an extension of the Standard Model featuring a hidden sector that consists of a new scalar charged under a new SU$(N)_D$ gauge group, singlet under all Standard Model gauge interactions, and coupled with the Standard Model only via…
Dark Higgs is very generic in dark matter models where DM is stabilized by some spontaneously broken dark gauge symmetries. Motivated by the FERMI observation of $\sim$GeV scale $\gamma$-ray excess from the galactic center (GC), we…
We consider electrically neutral complex vector particles $V$ below the GeV mass scale that, from a low energy perspective, couple to the photon via higher dimensional form factor interactions. We derive ensuing astrophysical constraints by…
Portal Matter, with both SM and dark charges, induces KM between the $U(1)_D$ dark photon and the SM gauge fields offering an attractive mechanism by which light thermal DM can obtain its observed relic density. If DM is fermionic, the CMB…
Recent LHC results suggest a standard model (SM)-like Higgs boson in the vicinity of 125 GeV with no clear indications yet of physics beyond the SM. At the same time, the SM is incomplete, since additional dynamics are required to…
A statistically significant excess of gamma rays has been reported and robustly confirmed in the Galactic Center over the past decade. Large local dark matter densities suggest that this Galactic Center Excess (GCE) may be attributable to…
We present a study of singlet-doublet vector-like leptonic dark matter (DM) in the framework of two Higgs doublet model (2HDM), where the dark sector is comprised of one doublet and one singlet vectorlike fermions (VLFs). The DM, that…
We introduce the spin-1 $U(1)_X$ gauged field $X$ with $Z_2$ odd dark parity to evade the current strong constraints on kinetic mixing. Then, $X$ becomes stable and a candidate for the dark matter. The lowest mass dimension of interaction…
We examine the possibility that dark matter (DM) consists of a gapped continuum, rather than ordinary particles. A Weakly-Interacting Continuum (WIC) model, coupled to the Standard Model via a Z-portal, provides an explicit realization of…