Related papers: Direct signals from electroweak singlets through t…
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…
We explore the possibility that the discrepancy in the observed anomalous magnetic moment of the muon $\Delta a _\mu$ and the predicted relic abundance of Dark Matter by Planck data, can be explained in a lepto-philic 2-HDM augmented by a…
Pulsars apparently missing from the galactic center could have been destroyed by asymmetric fermionic dark matter ($m_X = 1-100$ GeV) coupled to a light scalar ($m_{\phi}= 5-20$ MeV), which mixes with the Higgs boson. We point out that this…
The phenomenology of axions and axion-like particles strongly depends on their couplings to Standard Model particles. The focus of this paper is the phenomenology of the unique dimension six operator respecting the shift symmetry: the…
We provide a unified presentation of extensions of the Minimal Dark Matter framework in which new fermionic electroweak multiplets are coupled to each other via the Standard Model Higgs doublet. We study systematically the generic features…
We show that decoupled hidden sectors can have observational consequences. As a representative model example, we study dark matter production in the Higgs portal model with one real singlet scalar $s$ coupled to the Standard Model Higgs via…
A Higgs portal dark matter model for explaining the gamma-ray excess from the galactic center can be realized with the extension of local $SU(2)_X$ gauge symmetry with one quadruplet. Due to the residual $Z_3$ discrete symmetry of…
Though the 125-GeV scalar, as the Higgs boson of the standard model, is disfavoured as a dark matter portal by direct searches and the observations on relic density, a heavier scalar in an extended electroweak sector can fit into that role.…
One of the simplest extensions of the Standard Model is the Higgs portal extension involving a dark Higgs. Dark sectors that include dark matter candidates, WIMPs, axions, and dark photons, can naturally have this type of interaction, where…
Large classes of non-supersymmetric string models equipped with standard-model features have been constructed, but very little of their phenomenology is known. Interestingly, their spectra exhibit scalar fields whose only couplings to…
Dark matter (DM) is added to the Froggatt-Nielsen (FN) mechanism, and conditions for its successful freezeout identified. Requesting the FN scale $\Lambda_{\text{FN}}$ to be the cutoff of the theory renders freezeout scenarios surprisingly…
If dark matter is a new species of particle produced in the early universe as a cold thermal relic (a weakly-interacting massive particle-WIMP), its present abundance, its scattering with matter in direct-detection experiments, its…
We search for an extension of the Standard Model that contains a viable dark matter candidate and that can be embedded into a fundamental, asymptotically safe, quantum field theory with quantum gravity. Demanding asymptotic safety leads to…
We study the Dark Matter (DM) discovery prospect and its spin discrimination in the theoretical framework of gauge invariant and renormalizable Higgs portal DM models at the ILC with $\sqrt{s} = 500$ GeV. In such models, the DM pair is…
Thermal relic dark matter has been severely constrained in recent years by direct and indirect dark matter searches, as well as multi-messenger probes of dark sectors. At the current level of experimental precision, it has become difficult…
We test the dark photon as a portal connecting to the dark sector in the case of Dirac fermion and complex scalar dark matter with masses up to 1 TeV. Both the dark photon and the $Z$ boson contribute to the dark matter annihilation and…
Dark matter self-interactions can affect the small scale structure of the Universe, reducing the central densities of dwarfs and low surface brightness galaxies in accord with observations. From a particle physics point of view, this points…
We explore the Dirac fermionic and complex scalar dark matter in the framework of a hidden $\mathrm{U}(1)_\mathrm{X}$ gauge theory with kinetic mixing between the $\mathrm{U}(1)_\mathrm{X}$ and $\mathrm{U}(1)_\mathrm{Y}$ gauge fields. The…
A coupling of a scalar, charged under an unbroken global U(1) symmetry, to the Standard Model via the Higgs portal is one of the simplest gateways to a dark sector. Yet, for masses $m_{S}\geq m_{H}/2$ there are few probes of such an…
The QCD-like dark sector with GeV-scale dark hadrons has the potential to generate new signatures at the Large Hadron Collider (LHC). In this paper, we consider a singlet scalar mediator in the tens of GeV-scale that connects the dark…