Related papers: Neutrino Star as Galactic Cluster Dark Halo
Solar, atmospheric and reactor neutrino experiments established that neutrinos are massive. It is quite natural then to consider neutrinos as candidate particles for explaining the dark matter in halos around galaxies. We study the…
Observations of a flat density profile in the cores of dark-matter-dominated halos on the two extremes of mass for virialized objects in the universe, dwarf galaxies and galaxy clusters, present a serious challenge to the current standard…
Recent observations indicate that dark matter haloes have flat central density profiles. Cosmological simulations with non-baryonic dark matter predict however self similar haloes with central density cusps. This contradiction has lead to…
The standard cold dark matter (CDM) model has recently been challenged by the claim that dwarf galaxies have dark matter halos with constant density cores. Consequently, numerous alternative dark matter candidates have recently been…
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 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…
According to the now strongly supported concordance $\Lambda$CDM model, galaxies may be grossly described as a luminous component embedded in a dark matter halo. The density profile of these mass dominating haloes may be determined by N -…
One of the predictions of the standard CDM is that dark haloes have centrally divergent density profiles. An extensive body of rotation curve observations of dwarf and low surface brightness galaxies shows the dark haloes of those systems…
We present observations and analysis of rotation curves and dark matter halo density profiles in the central regions of four nearby dwarf galaxies. This observing program has been designed to overcome some of the limitations of other…
While N-body simulations testify for a cuspy profile of the central region of the dark matter haloes, observations favor a shallow, cored density profile of the central region of, at least, some spiral galaxies and dwarf spheroidals. We…
N-body simulations and analytical calculations of the gravitational collapse in an expanding universe predict that halos should form with a diverging inner density profile, the cusp. There are some observational indications that the dark…
In this paper we present strong evidence for a core in the density distribution of the dark halo around a (dwarf) galaxy. DDO 47 has a rotation curve that increases linearly from the first data point, at 300 pc, up to to the last one, at 5…
We discuss the structure of clusters in a class of flat cosmological models with the fraction of mass \Omega_{CDM} ~0.8 in cold dark matter, and the rest in hot dark matter in the form of massive neutrinos. We consider such Cold+Hot Dark…
Low Surface Brightness (LSB) galaxies are dominated by dark matter, and their rotation curves thus reflect their dark matter distribution. Recent high-resolution rotation curves suggest that their dark matter mass-density distributions are…
Simulations of the clustering of cold dark matter yield dark-matter halos that have central density cusps, but observations of totally dark-matter dominated dwarf spheroidal galaxies imply that they do not have cuspy central density…
In the past years a wealth of observations allowed to unravel the structural properties of the Dark Matter Halos around spirals. First, their rotation curves follow an Universal profile (URC) that can be described in terms of an exponential…
High-resolution N--body simulations show a remarkable similarity in the structure of dark matter halos formed through dissipationless hierarchical clustering. Independent of halo mass, power spectrum, and cosmological parameters, the…
The properties of substructure in galaxy clusters, exquisitely probed by gravitational lensing, offer a stringent test of dark matter (DM) models. Combining strong- and weak-lensing data for massive clusters, we map their total mass --…
A halo model is presented which possesses a constant phase space density (Q) core followed by a radial CDM-like power law decrease in Q. The motivation for the core is the allowance for a possible primordial phase space density limit such…
Cosmological N-body simulations predict that dark matter halos should have a universal shape characterized by a steep, cuspy inner profile. Here we report on a spectroscopic study of six clusters each containing a dominant brightest cluster…