Related papers: UltraViolet Freeze-in
Motivated by gauge coupling unification and dark matter, we present an extension to the Standard Model where both are achieved by adding an extra new matter multiplet. Such considerations lead to a Grand Unified Theory with very heavy…
Any form of dark matter which was in thermal equilibrium with the Standard Model in the early Universe must have some annihilation mechanism in order to avoid overclosure. In general, such models are now constrained by the negative…
We show that moduli fields as mediators between the Standard Model and the dark sector can naturally lead to the observed relic abundance. Indeed, even if moduli are very massive, the nature of their couplings with matter and gauge fields…
Non-thermalized dark matter is a cosmologically valid alternative to the paradigm of weakly interacting massive particles. For dark matter belonging to a $Z_2$-odd sector that contains in addition a thermalized mediator particle, dark…
We consider theories in which a dark sector is described by a Conformal Field Theory (CFT) over a broad range of energy scales. A coupling of the dark sector to the Standard Model breaks conformal invariance. While weak at high energies,…
We propose a novel mechanism for the cosmological production of keV - GeV mass dark matter that interacts with the Standard Model through a small effective magnetic dipole moment. Such an interaction can be radiatively generated if dark…
In the framework where the strong coupling is dynamical, the QCD sector may confine at a much higher temperature than it would in the Standard Model, and the temperature-dependent mass of the QCD axion evolves in a non-trivial way. We find…
Dark matter can be produced in the early universe via the freeze-in or freeze-out mechanisms. Both scenarios were investigated in references, but the production of dark matters via the combination of these two mechanisms are not addressed.…
We propose a new mechanism where a multi-component dark sector generates the observed dark matter abundance and baryon asymmetry and thus addresses the coincidence between the two. The thermal freeze-out of dark matter annihilating into…
We extend the Standard Model (SM) by introducing a $U(1)'$ gauge boson and a real pseudo-scalar field, both odd under a $\mathbb{Z}_2$ symmetry. The resulting low-energy spectrum consists of a stable vector as the dark matter candidate, and…
Freeze-in dark matter (DM) mediated by a light ($\ll$ keV) weakly-coupled dark-photon is an important benchmark for the emerging low-mass direct detection program. Since this is one of the only predictive, detectable freeze-in models, we…
Dark matter (DM) genesis via Ultraviolet (UV) freeze-in embeds the seed of reheating temperature and dynamics in its relic density. Thus, discovery of such a DM candidate can possibly open the window for post-inflationary dynamics. However,…
Dark Matter (DM) may belong to a hidden sector that is only feebly interacting with the Standard Model (SM) and may have never been in thermal equilibrium in the Early Universe. In this case, the observed abundance of dark matter particles…
We explore a new mechanism for reproducing the Dark Matter (DM) abundance: scatterings of one DM particle on light Standard Model particles. Strong bounds on its decays can be satisfied if DM undergoes freeze-in and has a mass around or…
We present a simplified version of the atomic dark matter scenario, in which charged dark constituents are bound into atoms analogous to hydrogen by a massless hidden sector U(1) gauge interaction. Previous studies have assumed that…
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…
We discuss the interplay between dark matter, leptogenesis and a new gauge boson $Z^\prime$ in the $B-L$ model. A fermion dark matter $\chi$ carrying $U(1)_{B-L}$ charge is introduced to the model but not coupling with other particles. We…
We consider the Standard Model (SM) extended by a secluded $U(1)_D$ gauge sector encompassing a Dirac fermion ($\chi$) dark matter (DM), an abelian gauge boson $Z^\prime$ and a SM-singlet complex-scalar field $\Phi$, whose radial component…
We propose a new paradigm for the thermal production of dark matter in the early universe, in which dark-matter particles acquire their mass and freeze out spontaneously from the thermal bath after a dark phase transition takes place. The…
The absence of any confirmative signals from extensive DM searching motivates us to go beyond the conventional WIMPs scenario. The feebly interacting massive particles (FIMPs) paradigm provides a good alternative which, despite of its…