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We model the mass distributions of 40 high surface brightness spiral galaxies inside their optical radii, deriving parameters of mass models by matching the predicted velocities to observed velocity maps. We use constant mass-to-light disk…

Astrophysics · Physics 2009-11-10 Eric I. Barnes , J. A. Sellwood , Arthur Kosowsky

A decade ago cosmological simulations of increasingly higher resolution were used to demonstrate that virialized regions of Cold Dark Matter (CDM) halos are filled with a multitude of dense, gravitationally-bound clumps. These dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Andrey V. Kravtsov

During hierarchical clustering, smaller masses generally collapse earlier than larger masses and so are denser on the average. The core of a small mass halo could be dense enough to resist disruption and survive undigested, when it is…

Astrophysics · Physics 2009-10-31 Kandaswamy Subramanian , Renyue Cen , Jeremiah P. Ostriker

We present density profiles, that are solutions of the spherical Jeans equation, derived under the following two assumptions: (i) the coarse grained phase-density follows a power-law of radius, rho/(sigma^3) proportional to r^{-alpha}, and…

Astrophysics · Physics 2009-11-07 Nicolaos Hiotelis

Astronomical observations strongly suggest that our universe is now accelerating and contains a substantial admixture of dark vacuum energy. Using numerical simulations to study this newly consolidated cosmological model (with a constant…

Astrophysics · Physics 2009-11-10 Fred C. Adams , Michael T. Busha , August E. Evrard , Risa H. Wechsler

Observations of density profiles of galaxies and clusters constrain the properties of dark matter. Formation of stable halos by collisional fluids with very low mass particles appears as the most probable interpretation, while halos formed…

General Physics · Physics 2011-04-14 Ernst Fischer

We examine the effects of mass resolution and force softening on the density profiles of cold dark matter halos that form within cosmological N-body simulations. As we increase the mass and force resolution, we resolve progenitor halos that…

Astrophysics · Physics 2009-10-30 Ben Moore , Fabio Governato , Tom Quinn , Joachim Stadel , George Lake

We present a new and completely general technique for calculating the fine-grained phase-space structure of dark matter throughout the Galactic halo. Our goal is to understand this structure on the scales relevant for direct and indirect…

Astrophysics · Physics 2009-11-13 Mark Vogelsberger , Simon D. M. White , Amina Helmi , Volker Springel

The cold dark matter (CDM) cosmology, which is the standard theory of the structure formation in the universe, predicts that the outer density profile of dark matter halos decreases with the cube of distance from the center. However, so far…

Astrophysics of Galaxies · Physics 2015-06-22 Takanobu Kirihara , Yohei Miki , Masao Mori

We present high-accuracy rotation curves, which show a steep nuclear rise and high-velocity central rotation, followed by a broad maximum in the disk and flat part. We use the rotation curves to directly calculate the radial distribution of…

Astrophysics · Physics 2007-05-23 Yoshiaki Sofue

Techniques for inferring the radial and geometric form of dark matter halos and the results they have produced to date are reviewed. Dark halos appear to extend to at least ~50 kpc with total enclosed masses that rise linearly with radius…

Astrophysics · Physics 2007-05-23 Penny D. Sackett

(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

I present an analysis of the density shapes of dark matter halos in LCDM and LWDM cosmologies. The main results are derived from a statistical sample of galaxy-mass halos drawn from a high resolution LCDM N-body simulation. Halo shapes show…

Astrophysics · Physics 2017-08-23 James S. Bullock

Analytical and geometrical properties of generalized power-law (GPL) density profiles are investigated in detail. In particular, a one-to-one correspondence is found between mathematical parameters and geometrical parameters. Then GPL…

Astrophysics · Physics 2009-11-10 R. Caimmi , C. Marmo , T. Valentinuzzi

The annihilation of dark matter particles in the halo of galaxies may end up into gamma rays, which travel almost unperturbed till to their detection at Earth. This annihilation signal can exhibit an anisotropic behavior quantified by the…

High Energy Astrophysical Phenomena · Physics 2014-06-19 F. Calore , V. De Romeri , M. Di Mauro , F. Donato , J. Herpich , A. V. Maccio' , L. Maccione

We consider dark masses measured from kinematic tracers at discrete radii in galaxies for which baryonic contributions to overall potentials are either subtracted or negligible. Recent work indicates that rotation curves due to dark matter…

Astrophysics of Galaxies · Physics 2015-05-18 Matthew G. Walker , Stacy S. McGaugh , Mario Mateo , Edward Olszewski , Rachel Kuzio de Naray

Virial mass is used as an estimator for the mass of a dark matter halo. However, the commonly used constant overdensity criterion does not reflect the dynamical structure of haloes. Here we analyze dark matter cosmological simulations in…

Astrophysics · Physics 2008-04-02 Antonio J. Cuesta , Francisco Prada

We have carried out a comparative analysis of the properties of dark matter halos in N-body and hydrodynamical simulations. We analyze their density profiles, shapes and kinematical properties with the aim of assessing the effects that…

Astrophysics · Physics 2009-10-30 P. B. Tissera , R. Dom\ci nguez-Tenreiro

We analyse the projected radial distribution of satellites around bright primary galaxies in the 2dFGRS. We have considered several primary-satellite subsamples to search for dependences of the satellite number density profile, \rho(r_p),…

Astrophysics · Physics 2009-11-10 Laura Sales , Diego G. Lambas

In an attempt to place an explicit constraint on dark matter models, we define and estimate a mean surface density of a dark halo within a radius of maximum circular velocity, which is derivable for various galaxies with any dark-matter…

Astrophysics of Galaxies · Physics 2015-06-24 Kohei Hayashi , Masashi Chiba
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