Related papers: Dark matter phase space densities
Collisionless particles, such as cold dark matter, interact only by gravity and do not have any associated length scale, therefore the dark halos of galaxies should have negligible core radii. This expectation has been supported by…
We have analyzed the rate of capture of dark matter (DM) particles by the galaxy in the case of the existence of two different types of DM or a bimodal velocity distribution function for DM. It is shown that, in addition to the scenario…
There is strong evidence that the mass in the Universe is dominated by dark matter, which exerts gravitational attraction but whose exact nature is unknown. In particular, all galaxies are believed to be embedded in massive haloes of dark…
In a spherically symmetric plasma constrained by its own gravity, the ionization degree lags behind changes in temperature and density. The ambipolar electric field accelerates ions radially and cools electrons. Ions lose energy and angular…
The severity of the mass discrepancy in spiral galaxies is strongly correlated with the central surface brightness of the disk. Progressively lower surface brightness galaxies have ever larger mass discrepancies. No other parameter…
Matter and dark matter in galaxies represent two main components linked by the gravitational interaction. Collisions of galaxies may create an offset between the centers of mass of these components. Ignoring internal dynamics of particles…
Dark matter density profiles based upon Lambda-CDM cosmology motivate an ansatz velocity distribution function with fewer high velocity particles than the Maxwell-Boltzmann distribution or proposed variants. The high velocity tail of the…
We present a synthesis of recent photometric and kinematic data for several of the most dark-matter dominated galaxies. There is a bimodal distribution in half-light radii, with stable star clusters always being smaller than $\sim30$pc,…
We analyze the intriguing possibility to explain both dark mass components in a galaxy: the dark matter (DM) halo and the supermassive dark compact object lying at the center, by a unified approach in terms of a quasi-relaxed system of…
If cold dark matter consists of particles, these must be non-interacting and non-relativistic by definition. In most cold dark matter models however, dark matter particles inherit a non-vanishing velocity dispersion from interactions in the…
Mass bounds on dark matter (DM) candidates are obtained for particles decoupling in or out of equilibrium with {\bf arbitrary} isotropic and homogeneous distribution functions. A coarse grained Liouville invariant primordial phase space…
In unified field theory the cosmological model of the universe has supersymmetric fields. Supersymmetric particles as dark and normal matter in galaxy clusters have a phase separation. Dark matter in halos have a statistical physics…
The distribution of the stellar and gaseous components in low surface brightness galaxies has been determined directly from optical and HI imaging. The distribution of what might be the dominant mass component, the dark matter, which is…
There are observational and theoretical indications that both the visible (stars) and the dark matter density distributions in elliptical galaxies increase significantly up to the galactic center. I present here some analytical results…
Gravitational collapse of dark matter, merger of dark matter haloes and tidal disruption of satellites are among processes which lead to the formation of fine and dense dark matter shells, also known as dark matter caustics. The putative…
The distributions of dark matter and baryons in the Universe are known to be very different: the dark matter resides in extended halos, while a significant fraction of the baryons have radiated away much of their initial energy and fallen…
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…
Low mass surface density spiral and irregular galaxies like low surface brightness (LSB) and dwarf galaxies are unique laboratories to study the dynamical properties of Dark Matter halos because their mass is generally dominated by dark…
Dark matter particles may be captured by a star and then thermalized in the star's core. At the end of its life a massive star collapses suddenly and a compact object is formed. The dark matter particles redistribute accordingly. In the…
Cosmological N-body simulations were performed to study the evolution of the phase-space density Q = rho/sigma^3 of dark matter halos. No significant differences in the scale relations Q ~ sigma^(-2.1) or Q ~ M^(-0.82) are seen for "cold"…