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Related papers: Low mass dark matter halos in voids

200 papers

We study the effects of mass and force resolution on the density profiles of galaxy-size Cold Dark Matter (CDM) halos in a flat, low-density cosmological model with vacuum energy. We show thatalthough increasing the mass and force…

Astrophysics · Physics 2008-11-26 Anatoly Klypin , Andrey V. Kravtsov , James Bullock , Joel Primack

We present the germ of a new model for High Velocity Clouds, derived from the idea that the dark matter halo of our Galaxy is in the form of cold, planetary-mass gas clouds. In this picture HVCs arise as a result of disruptive collisions…

Astrophysics · Physics 2007-05-23 Mark Walker , Mark Wardle

The thickness of the neutral hydrogen layer, coupled with the rotation curve, traces the outer dark matter potential. We estimate the amplitude of the flaring in spiral galaxies from a 3D model of the HI gas. Warps in particular are…

Astrophysics · Physics 2007-05-23 J. -F. Becquaert , F. Combes

We present a detailed non-spherical modeling of dark matter halos on the basis of a careful analysis of state-of-the art N-body simulations. The fitting formulae presented here form a complete and accurate description of the triaxial…

Astrophysics · Physics 2007-05-23 Y. P. Jing

We use simulations of the formation and evolution of the galaxy population in the Local Universe to address the issue of whether the standard theoretical model succeeds in producing empty regions as large and as dark as the observed nearby…

Astrophysics · Physics 2009-11-07 H. Mathis , S. D. M. White

I show that the predicted densities of the inner dark matter halos in LCDM models of structure formation appear to be higher than estimates from real galaxies and constraints from dynamical friction on bars. This inconsistency would not be…

Astrophysics · Physics 2015-05-13 J. A. Sellwood

We build a simple analytical model for the bias of dark matter halos that applies to objects defined by an arbitrary density threshold, $200\leq\deltas\leq 1600$, and that provides accurate predictions from low-mass to high-mass halos. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Patrick Valageas

Lyman limit and damped Lyman-alpha absorption systems probe the distribution of collapsed, cold gas at high redshift. Numerical simulations that incorporate gravity and gas dynamics can predict the abundance of such absorbers in…

Astrophysics · Physics 2009-10-28 Jeffrey P. Gardner , Neal Katz , Lars Hernquist , David H. Weinberg

We derive the density profile of cold dark matter halos using a self-similar accretion model. We show that if the clumpiness of the infalling matter is taken into account, then the inner density slope, d(log{rho})/d(log{r}), is close to -1.…

Astrophysics · Physics 2007-05-23 Leonid Chuzhoy

(Abridged) Using high-resolution cosmological N-body simulations, we study how the density profiles of dark matter halos are affected by the filtering of the density power spectrum below a given scale length and by the introduction of a…

Astrophysics · Physics 2009-09-25 V. Avila-Reese , P. Colin , O. Valenzuela , E. D'Onghia , C. Firmani

How do observed voids relate to the underlying dark matter distribution? To examine the spatial distribution of dark matter contained within voids identified in galaxy surveys, we apply Halo Occupation Distribution models representing…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 P. M. Sutter , Guilhem Lavaux , Benjamin D. Wandelt , David H. Weinberg , Michael S. Warren

We study the angular momentum profile of dark matter halos for a statistical sample drawn from a set of high-resolution cosmological simulations of $256^3$ particles. Two typical Cold Dark Matter (CDM) models have been analyzed, and the…

Astrophysics · Physics 2009-11-07 D. N. Chen , Y. P. Jing

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…

Astrophysics · Physics 2007-07-11 Laurent Chemin , Claude Carignan , Philippe Amram

We compare the central mass concentration of Cold Dark Matter halos found in cosmological N-body simulations with constraints derived from the Milky Way disk dynamics and from the Tully-Fisher relation. For currently favored values of the…

Astrophysics · Physics 2009-09-28 Julio F. Navarro , Matthias Steinmetz

We present results from a detailed dynamical analysis of five high surface brightness, late type spirals, studied with the aim to quantify the luminous-to-dark matter ratio inside their optical radii. The galaxies' stellar light…

Astrophysics · Physics 2009-11-07 Thilo Kranz , Adrianne Slyz , Hans-Walter Rix

We present the results of a study of weak lensing by galaxies based on 45.5 deg$^2$ of $R_C$ band imaging data from the Red-Sequence Cluster Survey (RCS). We present the first weak lensing detection of the flattening of galaxy dark matter…

Astrophysics · Physics 2008-11-26 Henk Hoekstra , Howard K. C. Yee , Michael D. Gladders

We measure the mass function of dark matter halos in a large set of collisionless cosmological simulations of flat LCDM cosmology and investigate its evolution at z<~2. Halos are identified as isolated density peaks, and their masses are…

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 consider a self-gravitating ideal fermion gas at nonzero temperature as a model for the Galactic halo. The Galactic halo of mass ~ 2 x 10^12 Msol enclosed within a radius of ~ 200 kpc implies the existence of a supermassive compact dark…

Astrophysics · Physics 2007-05-23 Neven Bilic , Gary B. Tupper , Raoul D. Viollier

Using high resolution DM simulations we study the shape of dark matter halos. Halos become more spherical with decreasing mass. This trend is even more pronounced for the inner part of the halo. Angular momentum and shape are correlated.…

Astrophysics · Physics 2009-11-11 Stefan Gottloeber , Victor Turchaninov