相关论文: Comment on the dispersion-velocity of galactic dar…
In a recent Letter (astro-ph/9605001), Cowsik et al. claim that a self-consistent treatment of the dark Galactic halo requires that the local velocity dispersion of dark-matter particles be $600$ km~s$^{-1}$ or greater, more than a factor…
In a recent Letter (astro-ph/9605001), Cowsik et al. claim that the best fit value of the velocity dispersion of the Galactic dark matter is 600 kms. This result is obtained by a numerical method of solving the coupled self-gravitation…
The self-consistent spatial distribution of particles of Galactic dark matter is derived including their own gravitational potential, as also that of the visible matter of the Galaxy. In order to reproduce the observed rotation curve of the…
The velocity distribution of the dark matter particles on the outskirts of the Solar System remains unclear. We suggest to determine it using experimentally found properties of the oldest halo objects. Indeed, the oldest halo stars and…
We use high-quality optical rotation curves of 9 low-luminosity disk galaxies to obtain the velocity profile of the surrounding dark matter halos. We find that they increase linearly with radius at least out to the stellar disk edge,…
We derive the pairwise peculiar velocity distribution function of dark matter particles applying the dark matter halo approach. Unlike the previous work, we do not assume a Gaussian velocity distribution function of dark matter in a single…
Celestial capture of dark matter provides a useful handle for constraining its particulate properties. The capture formalism is sensitive to the phase space distribution of dark matter in the vicinity of the celestial object. This article…
It is a well-known fact that the gravitational effect of dark matter in galaxies is only noticeable when the orbital accelerations drop below $a_0 \simeq 2\times 10^{-8}$ cm s$^{-1}$ (Milgrom's Law). This peculiarity of the dynamic…
We present a new method to construct fully self-consistent equilibrium models of multi-component disc galaxies similar to the Milky Way. We define distribution functions for the stellar disc and dark halo that depend on phase space position…
We review the most recent evidence for the amazing properties of the density distribution of dark matter around spiral galaxies. Their rotation curves, coadded according to the galaxy luminosity, conform to an universal profile which can be…
The dark matter subhalos orbiting in a galactic halo perturb the orbits of stars in thin stellar streams. Over time the random velocities in the streams develop non-Gaussian wings. The rate of velocity increase is approximately a random…
We present a simple model that accurately describes various statistical properties of peculiar velocities of dark matter halos. We pay particular attention to the following two effects; first, the evolution of the halo peculiar velocity…
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 use the recently completed one billion particle Via Lactea II LambdaCDM simulation to investigate local properties like density, mean velocity, velocity dispersion, anisotropy, orientation and shape of the velocity dispersion ellipsoid,…
We show that the observed upper bound on the line-of-sight velocity dispersion of the stars in an early-type galaxy, sigma<400km/s, may have a simple dynamical origin within the LCDM cosmological model, under two main hypotheses. The first…
The standard method of measuring the galaxy pairwise velocity dispersion on small scales is heavily weighted by the densest regions in a way that is difficult to calibrate. We propose a new statistic which measures the small-scale velocity…
The distributions of normal matter and of dark matter in the Galaxy are coupled to each other as they both move in the common gravitational potential. In order to fully exploit this interplay and to derive the various properties of dark…
We investigate the evolution in the dark matter halo circular velocity function, measured at a fixed physical radius of 20 kpc (v_20), which is likely to be a good proxy for galaxy circular velocity, in the Millennium-II simulation. We find…
We analyze the Illustris-1 hydrodynamical cosmological simulation to explore the stellar velocity dispersion of quiescent galaxies as an observational probe of dark matter halo velocity dispersion and mass. Stellar velocity dispersion is…
We examine the amplitude of the rotation velocity that can be attributed to the dark matter halos of disk galaxies, focusing on well measured intermediate radii. The data for 60 galaxies spanning a large range of mass and Hubble types,…