Related papers: Long live the Higgs portal!
Higgs-portal effective field theories are widely used as benchmarks in order to interpret collider and astroparticle searches for dark matter (DM) particles. To assess the validity of these effective models, it is important to confront them…
We constrain the Higgs-portal model employing the vector-boson fusion channel at the LHC. In particular, we include the phenomenologically interesting parameter region near the Higgs resonance, where the Higgs-boson mass is close to the…
This work considers an extension of the Standard Model (SM) Higgs sector by a real, scalar singlet field, including applicability to a dark matter (DM) model with the addition of a Yukawa coupling to a Dirac fermion. The collider signatures…
The left-right twin Higgs model predicts a light stable scalar \hat{S}, which is a candidate for WIMP dark matter. We study its scattering on nucleon and find that the cross section is below the CDMS II upper bound but can reach the…
We present a hidden Abelian extension of the Standard Model including a complex scalar as a dark matter candidate and a light scalar acting as a long range force carrier between dark matter particles. The Sommerfeld enhanced annihilation…
We study freeze-in production of Higgs portal dark matter (DM) at temperatures far below the dark matter mass. The temperature of the Standard Model (SM) thermal bath may have never been high such that dark matter production via thermal…
We investigate a two-component dark matter scenario in the type-I two-Higgs-doublet model. The dark sector contains a real scalar $s$ and a Dirac fermion $\chi$, whose stability is ensured by a $Z_4$ symmetry together with kinematic…
The particle nature of dark matter (DM) remains one of the central open problems in modern physics. Among the most extensively studied candidates are weakly interacting massive particles, whose parameter space is now under strong pressure…
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 show that the mass of a self-interacting dark matter candidate, specifically a Dirac fermion, can be generated by composite dynamics, with a light scalar mediator emerging alongside the Higgs itself as composite particles. These novel…
Dark matter candidates arising in models of particle physics incorporating weak scale supersymmetry may produce detectable signals through their annihilation into neutrinos, photons, or positrons. A large number of relevant experiments are…
Due to the strong constrain from the LUX experiment, the scalar portal dark matter can not generally explain a gamma-ray excess in the galactic center by the annihilation of dark matter into $b\bar{b}$. With the motivation of eliminating…
Weakly-coupled TeV-scale particles may mediate the interactions between normal matter and dark matter. If so, the LHC would produce dark matter through these mediators, leading to the familiar "mono-X" search signatures, but the mediators…
We examine Simplified Models in which fermionic DM interacts with Standard Model (SM) fermions via the exchange of an $s$-channel scalar mediator. The single-mediator version of this model is not gauge invariant, and instead we must…
We consider the Singlet Majorana fermion dark matter model, in which the standard model particles interact with the dark sector through the mixing of a singlet scalar and the Higgs boson. In this model both the dark matter and the singlet…
Astrophysical observations provide compelling evidence for gravitationally interacting dark matter in the universe that cannot be explained by the standard model of particle physics. The extraordinary amount of data from the CERN LHC…
The Higgs-portal model with a singlet scalar Dark Matter particle is one of the simplest extensions to the Standard Model that can reproduce the relic density. Unfortunately this model is strongly constrained by direct and indirect DM…
Higgs decays displaced from the primary interaction vertex represent a striking experimental signature that is actively searched for by the ATLAS, CMS and LHCb collaborations. We point out that signals of this type appear in the context of…
Dark matter could emerge along with the Higgs as a composite pseudo-Nambu-Goldstone boson $\chi$ with decay constant $f\sim \mathrm{TeV}$. This type of WIMP is especially compelling because its leading interaction with the Standard Model,…
We consider a hidden sector dark matter, where a singlet fermion is a cold dark matter and a real singlet scalar boson $S$ is a messenger between the SM and the hidden sectors. This singlet scalar will mix with the SM Higgs boson $h$, and…