Related papers: Limits on Early Matter Domination from the Isotrop…
The PAMELA, Fermi and HESS experiments (PFH) have shown anomalous excesses in the cosmic positron and electron fluxes. A very exciting possibility is that those excesses are due to annihilating dark matter (DM). In this paper we calculate…
Cosmological observations precisely measure primordial variations in the density of the Universe at megaparsec and larger scales, but much smaller scales remain poorly constrained. However, sufficiently large initial perturbations at small…
We suggest a dark matter scenario which could contribute the possible anomaly observed by Fermi-LAT $\gamma$-ray space telescope. It is based on the model recently proposed by Weinberg. In our scenario the gamma-ray line signal comes from…
We consider the diffuse gamma ray data from FERMI first year observations and compare them to the gamma ray fluxes predicted by Dark Matter annihilation or decay (both from prompt emission and from Inverse Compton Scattering), for different…
Decoupled hidden sectors can easily and generically result in a period of cannibal domination, during which the dominant component of the Universe has an equation of state intermediate between radiation and matter due to self-heating by…
We propose that dark matter is dominantly comprised of atomic bound states. We build a simple model and map the parameter space that results in the early universe formation of hydrogen-like dark atoms. We find that atomic dark matter has…
We revisit the impact of early dark energy (EDE) on galaxy clustering using BOSS galaxy power spectra, analyzed using the effective field theory (EFT) of large-scale structure (LSS), and anisotropies of the cosmic microwave background (CMB)…
The gamma-ray line from dark matter (DM) annihilation is too weak to observe, but its observation will uncover much information, e.g., the DM mass and an nomalously large annihilation rate $\sim0.1$ pb into di-photon. In this work, we…
A wide range of mechanisms predict present-day s-wave dark matter (DM) annihilation cross-sections that are orders of magnitude below current experimental sensitivity. We explore the capability of DM density spikes around the Milky Way's…
We suggest that an interplay between microscopic and macroscopic physics can give rise to dark matter (DM) whose interactions with the visible sector fundamentally undulate in time, independent of celestial dynamics. A concrete example is…
Any particle dark matter (DM) scenario featuring a suppressed power spectrum of astrophysical relevance results in a delay of galaxy formation. As a consequence, such scenarios can be constrained using the global 21-cm absorption signal…
We derive bounds on the dark matter annihilation cross-section for low-mass (5-20 GeV) dark matter annihilating primarily to up or down quarks, using the Fermi-LAT bound on gamma-rays from Milky Way satellites. For models in which dark…
Despite the great progress of current cosmological measurements, the nature of the dominant component of the universe, coined dark energy, is still an open question. Early Dark Energy is a possible candidate which may also alleviate some…
We study the flux and the angular power spectrum of gamma-rays produced by Dark Matter (DM) annihilations in the Milky Way (MW) and in extra-galactic halos. The annihilation signal receives contributions from: a) the smooth MW halo, b)…
Dwarf spheroidal galaxies (dSphs) are promising targets for the indirect detection of dark matter through gamma-ray emission due to their proximity, lack of astrophysical backgrounds and high dark matter density. They are often used to…
Exploring the realm of Dark Matter research, Light DM, which has a mass in the range of 1 MeV to 1 GeV, is a fascinating topic both theoretically and experimentally. We assume that the light dark matter is composed of complex scalars and…
Early-matter-like dark energy is defined as a dark energy component whose equation of state approaches that of cold dark matter (CDM) at early times. Such a component is an ingredient of unified dark matter (UDM) models, which unify the…
We investigate the influence of an early matter-dominated era in cosmic history on the dynamics of cosmic strings and the resulting stochastic gravitational waves. Specifically, we examine the case where this era originates from the dark…
Several nearby ultra-faint satellites of the Milky Way discovered by the Dark Energy Survey (DES) during the last few years are promising targets for indirect dark matter (DM) searches with very-high-energy (VHE, E$\gtrsim$100 GeV) gamma…
One of the predictions of the $\Lambda$CDM cosmological framework is the hierarchical formation of structure, giving rise to dark matter (DM) halos and subhalos. When the latter are massive enough they retain gas (i.e., baryons) and become…