Related papers: Warm Dark Matter from keVins
We propose a minimal, ultraviolet-complete, and renormalizable extension of the Standard Model, in which the three generations of ordinary fermions are distinguished by family-dependent hypercharges, while three right-handed neutrinos are…
Supersymmetric extensions of the Standard Model that incorporate the axion solution to the strong CP problem necessarily contain also the axino, the fermionic partner of the axion. In contrast to the neutralino and the gravitino, the axino…
All presently known stellar-dynamical constraints on the size and mass of the supermassive compact dark object at the Galactic center are consistent with a ball of self-gravitating, nearly non-interacting, degenerate fermions with mass…
As experimental null results increase the pressure on heavy weakly interacting massive particles (WIMPs) as an explanation of thermal dark matter (DM), it seems timely to explore previously overlooked regions of the WIMP parameter space. In…
We present a model where sterile neutrinos with rest masses in the range ~ keV to ~ MeV can be the dark matter and be consistent with all laboratory, cosmological, large-scale structure, as well as x-ray constraints. These sterile neutrinos…
The axino is a promising candidate for dark matter in the Universe. It is electrically and color neutral, very weakly interacting, and could be - as assumed in this study - the lightest supersymmetric particle, which is stable for unbroken…
Many independent high resolution simulations have indicated that the standard collisionless cold dark matter model does not reproduce the structure of observed present day galaxies well. Several possible solutions in the form of…
Both active and sterile sub-eV neutrinos can serve for hot dark matter (DM). On the other hand, keV sterile neutrinos could be a good candidate for warm DM. The beta-decaying (e.g., H-3 and Ru-106) and EC-decaying (e.g., Ho-163) nuclei are…
We study a scalar singlet dark matter (DM) having mass in sub-TeV regime by extending the minimal scalar singlet DM setup by additional vector like fermions. While the minimal scalar singlet DM satisfies the relic and direct detection…
The minimal seesaw extension of the Standard Model requires two electroweak singlet fermions in order to accommodate the neutrino oscillation parameters at tree level. Here we consider a next to minimal extension where light neutrino masses…
The neutrino mass generation mechanism, the nature of dark matter and the origin of the baryon asymmetry of the Universe are three compelling questions that cannot be accounted for in the Standard Model of particle physics. In this thesis…
We study the possibility of singlet fermion dark matter (DM) and successful leptogenesis in minimal scotogenic model which also provides a common origin of DM and light neutrino masses. In this scenario, where the standard model (SM) is…
Supersymmetric extensions of the Standard Model when combined with the Peccei-Quinn solution to the strong CP problem necessarily contain also the axino, the fermionic partner of the axion. In contrast to the neutralino and the gravitino,…
Weakly Interacting Massive Particles (WIMPs) and axions are arguably the most compelling dark matter candidates in the literature. Could they coexist as dark matter particles? More importantly, can they be incorporated in a well motivated…
We show that novel paths to dark matter generation and baryogenesis are open when the Standard Model is extended with three sterile neutrinos $N_i$ and a charged scalar $\delta^+$. Specifically, we propose a new production mechanism for the…
We solve the cosmological evolution of warm dark matter (WDM) density fluctuations with the Volterra integral equations of paper I. In the absence of neutrinos, the anisotropic stress vanishes and the Volterra equations reduce to a single…
Thermal relics lighter than an MeV contribute to the energy density of the universe at the time of nucleosynthesis and recombination. Constraints on extra radiation degrees of freedom typically exclude even the simplest of such dark…
A very light boson of mass $\mathcal{O}(10^{-22})$ eV may potentially be a viable dark matter (DM) candidate which can avoid phenomenological problems associated with cold DM. Such "fuzzy DM (FDM)" may naturally be an axion with a decay…
Assuming that mass scales arise in nature only via dimensional transmutation, we extend the dimension-less Standard Model by adding vector-like fermions charged under a new strong gauge interaction. Their non-perturbative dynamics generates…
Thermal freeze-out is a prominent example of dark matter (DM) production mechanism in the early Universe that can yield the correct relic density of stable weakly interacting massive particles (WIMPs). At the other end of the mass scale,…