Related papers: Radiative corrections to vectorlike portal dark ma…
If dark matter (DM) annihilation accounts for the tantalizing excess of cosmic ray electron/positrons, as reported by the PAMELA, ATIC, HESS and FERMI observatories, then the implied annihilation cross section must be relatively large. This…
We discuss a simple extension of the Standard Model (SM) that provides an explicit realization of the dark-matter (DM) neutrino-portal paradigm. The dark sector is composed of a scalar $ \Phi $ and a Dirac fermion $ \Psi $, with the latter…
We study direct detection in simplified models of Dark Matter (DM) in which interactions with Standard Model (SM) fermions are mediated by a heavy vector boson. We consider fully general, gauge-invariant couplings between the SM, the…
Multi-component dark matter scenarios constitute natural extensions of standard single-component setups and offer attractive new dynamics that could be adopted to solve various puzzles of dark matter. In this work we present and illustrate…
We introduce a simple scenario involving fermionic dark matter ($\chi$) and singlet scalar mediators that may account for the Galactic Center GeV $\gamma$-ray excess while satisfying present direct detection constraints. CP-violation in the…
Sterile neutrinos could provide a link between the Standard Model particles and a dark sector, besides generating active neutrino masses via the seesaw mechanism type I. We show that, if dark matter annihilation into sterile neutrinos…
We consider the scenario in the radiative seesaw model where the dark matter particle is the lightest $Z_2$-odd fermion. We identify the regions of the parameter space of the model compatible with neutrino oscillation data, with the upper…
Recently, it has been shown that electrons and positrons from dark matter (DM) annihilations provide an excellent fit to the Fermi, PAMELA, and HESS data. Using this DM model, which requires an enhancement of the annihilation cross section…
We propose a renormalizable model of a fermionic dark matter by introducing a gauge singlet Dirac fermion and a real singlet scalar. The bridges between the singlet sector and the standard model sector are only the singlet scalar…
Dark matter annihilations have been fiercely restricted by the non-observation of excess events in indirect detection probes. Typically the interactions that dictate annihilation are also present in the dark matter-nucleon scattering cross…
Inspired by the excess of gamma rays from the Galactic Center, we confront a number of simplified dark matter models with experimental data. Assuming a single dark matter particle coupled to standard matter via a spin-0 mediator, we compare…
In this work, we study an extension of the Standard Model which includes a new massive vector field in the fundamental representation of SU(2)_L. The neutral component of the new vector field is a natural dark matter candidate. We compute…
An extension of the Standard Model with a hidden sector which consists of gauge singlets (a Dirac fermion $\chi$ and a scalar $S$) plus a vector boson $V_\mu$ (dark massive photon) is studied. The singlet scalar interacts with the Standard…
The hypothesis of dark matter interacting with the standard model uniquely via the Higgs portal is severely challenged by experiments. However, if dark matter is a fermion, the Higgs-portal interaction implies the presence of mediators,…
A recently proposed dark matter WIMP has only second-order couplings to gauge bosons and itself. As a result, it has small annihilation, scattering, and creation cross-sections, and is consequently consistent with all current experiments…
We have built a lepton-specific next-to-minimal two-Higgs-doublet-portal vector dark matter model. The vector dark matter in the hidden sector does not directly couple to the visible sector, but instead annihilates into the hidden Higgs…
Basic idea of this analysis is to achieve a two-component dark matter (DM) framework composed of a scalar and a fermion, with non-negligible DM-DM interaction contributing to thermal freeze out (hence relic density), but hiding them from…
We make a comprehensive study of vector-like fermionic dark matter and flavor anomalies in a simple extension of standard model. The model is added with doublet vector-like fermions of quark and lepton types, and also a…
In Higgs portal models of fermion dark matter, scalar couplings are unavoidably suppressed by strong bounds from direct detection experiments. As a consequence, thermal dark matter relics must coexist with mediators in a compressed spectrum…
We show that the $\mathinner{\mathrm{GeV}}$ scale $\gamma$-ray excess from the direction of the Galactic Center can be naturally explained by the pair annihilation of Abelian vector dark matter (VDM) into a pair of dark Higgs bosons $VV…