相关论文: Decaying Dark Matter and the Deficit of Dwarf Halo…
The paucity of observed dwarf galaxies in the Local Group relative to the abundance of predicted dark matter halos remains one of the greatest puzzles of the LCDM paradigm. Solving this puzzle now requires not only matching the numbers of…
The standard cold dark matter (CDM) model predicts too many and too dense small structures. We consider an alternative model that the dark matter undergoes two-body decays with cosmological lifetime $\tau$ into only one type of massive…
The dark energy plus cold dark matter ($\Lambda$CDM) cosmological model has been a demonstrably successful framework for predicting and explaining the large-scale structure of Universe and its evolution with time. Yet on length scales…
We present results of cosmological N-body hydrodynamic chemistry simulations of primordial structure growth and evolution in a scenario with warm dark matter (WDM) having a mass of 3 keV (thermal relic) and compare with a model consisting…
We speculate that the dark halos of dwarf galaxies and low surface brightness galaxies soften their central cusps by the decay of a fraction of cold dark matter (CDM) particles to a stable particle with a recoiling velocity of a few tens km…
We present zoom-in N-body + Hydrodynamic simulations of dwarf central galaxies formed in Warm Dark Matter (WDM) halos with masses at present-day of $2-4\times 10^{10}$ \msun. Two different cases are considered, the first one when halo…
It is now established that several of the Local Group dwarf Spheroidal galaxies (dSphs) have large mass-to-light ratios. We consider the possibility that the dark matter in the halos of dSphs is composed of massive black holes with masses…
We use the ``Via Lactea'' simulation to study the co-evolution of a Milky Way-size LambdaCDM halo and its subhalo population. While most of the host halo mass is accreted over the first 6 Gyr in a series of major mergers, the physical mass…
Although most proposed dark matter candidates are stable, in order for dark matter to be present today, the only requirement is that its lifetime is longer than the age of the Universe, t_U ~ 4 10^17 s. Moreover, the dark matter particle…
$\Lambda$CDM-model predicts an excess of dark halos compared to the observations. The excess is seen from the estimates of the virialized mass inside the Local Supercluster and its surroundings. It is shown that account for cosmological…
In this Letter we investigate the basic assumptions of the decaying dark matter (DDM) theory in the light of recent advances in observational and theoretical cosmology and physics, i.e. detection of massive astrophysical compact halo…
A possibility of DM being multicomponent has a strong implication on resolving decades-long known cosmological problems on small scale. In addition to elastic scattering, the model allows for inelastic interactions, which can be…
In this review we outline the major points of ab-initio cosmological models focusing on some galaxy evolution unresolved problems. In particular our knowledge of the star formation rate which leads galaxy evolution, i.e. luminosity, colors…
In the standard cosmological model a mysterious cold dark matter (CDM) component dominates the formation of structures. Numerical studies of the formation of CDM halos have produced several robust results that allow unique tests of the…
In this paper we examine aspects of primordial star formation in a gravitino warm dark matter universe with a cosmological constant. We compare a set of simulations using a single cosmological realization but with a wide range of warm dark…
In a purely cold dark matter universe, the initial matter power spectrum and its subsequent gravitational growth contain no special mass- or time-scales, and so neither do the emergent population statistics of internal dark matter (DM) halo…
Much evidence suggests that we live in a flat Cold Dark Matter universe with a cosmological constant. Accurate analytic formulae are now available for many properties of the dark halo population in such a Universe. Assuming current…
We use N-body simulations to investigate the structure of dark halos in the standard Cold Dark Matter cosmogony. Halos are excised from simulations of cosmologically representative regions and are resimulated individually at high…
Dark matter (DM) halos of Sc-Im and dwarf spheroidal (dSph) galaxies satisfy scaling laws: halos in lower-luminosity galaxies have smaller core radii, higher central densities, and smaller velocity dispersions. These results are based on…
The JWST mission is in the process of probing the galaxy mass function at $z>10$, when conceivably any delay in halo assembly due to the presence of a dwarf galaxy-scale power spectrum cutoff may drastically suppress the number of galaxies…