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Related papers: Caustics in Dark Matter Haloes

200 papers

We examine the effect of primordial dark matter velocity dispersion and/or particle self-interactions on the structure and stability of galaxy halos, especially with respect to the formation of substructure and central density cusps.…

Astrophysics · Physics 2009-10-31 Craig J. Hogan , Julianne J. Dalcanton

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 -…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-04 A. Del Popolo , V. F. Cardone

For nearly 40 years, dark matter has been widely assumed to be cold and collisionless. Cold dark matter models make fundamental predictions for the behavior of dark matter on small (<10 kpc) scales. These predictions include cuspy density…

We prove that a flow of cold collisionless particles from all directions in and out of a region necessarily forms a caustic. A corollary is that, in cold dark matter cosmology, galactic halos have inner caustics in addition to the more…

Astrophysics · Physics 2009-11-13 Aravind Natarajan , Pierre Sikivie

Estimating collision rates is of immense importance in particle-laden flows. An economical way of doing this is to directly identify incidences of caustics, or extreme clustering, by tracking particle velocity gradients in the neighborhoods…

Fluid Dynamics · Physics 2026-01-21 C. Rajarshi , Rama Govindarajan

We estimate the two-point correlation function of dark matter haloes, with masses >10^{13} h^{-1} Mo, that have or not significant substructure. The haloes are identified with a friends of friends algorithm in a large LCDM simulation at two…

Astrophysics · Physics 2009-11-13 N. Espino-Briones , M. Plionis , C. Ragone-Figueroa

We investigate the structure of the dark matter halo formed in the cold dark matter scenarios by N-body simulations with parallel treecode on GRAPE cluster systems. We simulated 8 halos with the mass of $4.4\times 10^{14}M_{\odot}$ to…

Astrophysics · Physics 2009-11-07 Toshiyuki Fukushige , Atsushi Kawai , Junichiro Makino

We use a cosmological simulation of the Local Group to make quantitative and speculative predictions for direct detection experiments. Cold dark matter (CDM) halos form via a complex series of mergers, accretion events and violent…

We study the phase-space structure of a dark-matter halo formed in a high resolution simulation of a Lambda CDM cosmology. Our goal is to quantify how much substructure is left over from the inhomogeneous growth of the halo, and how it may…

Astrophysics · Physics 2009-09-25 Amina Helmi , Simon D. M. White , Volker Springel

Cosmological structure formation predicts that our galactic halo contains an enormous hierarchy of substructures and streams, the remnants of the merging hierarchy that began with tiny Earth mass microhalos. If these structures persist…

Astrophysics of Galaxies · Physics 2015-03-19 Aurel Schneider , Lawrence M. Krauss , Ben Moore

We present the first and so far the only simulations to follow the fine-grained phase-space structure of galaxy haloes formed from generic LCDM initial conditions. We integrate the geodesic deviation equation in tandem with the N-body…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Mark Vogelsberger , Simon D. M. White

The shapes of individual self-gravitating structures of an ensemble of identical, collisionless particles have remained elusive for decades. In particular, a reason why mass density profiles like the Navarro-Frenk-White or the Einasto…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-01 Jenny Wagner

We use very high resolution cosmological zoom simulations to follow the early evolution of twelve first-generation haloes formed from gaussian initial conditions with scale-free power spectra truncated on small scales by a gaussian in…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-29 M. Sten Delos , Simon D. M. White

Clumping of elementary dark matter in the Galaxy halo may be inevitable. If so, the nondetection of certain dark matter candidates could simply mean that the local halo density is low. Conversely, indirect detection of annihilation products…

Astrophysics · Physics 2007-05-23 Ira Wasserman

We have identified over 2000 well resolved cluster halos, and also their associated bound subhalos, from the output of a 1024^3 particle cosmological N-body simulation (of box size 320 h^-1 Mpc and softening length 3.2 h^-1 kpc). This has…

Astrophysics · Physics 2010-11-11 L. D. Shaw , J. Weller , J. P. Ostriker , P. Bode

We investigate unbound dark matter particles in halos by tracing particle trajectories in a simulation run to the far future (a = 100). We find that the traditional sum of kinetic and potential energies is a very poor predictor of which…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-26 Peter S. Behroozi , Abraham Loeb , Risa H. Wechsler

A defining prediction of the cold dark matter (CDM) cosmological model is the existence of a very large population of low-mass haloes. This population is absent in models in which the dark matter particle is warm (WDM). These alternatives…

The first dark matter halos form by direct collapse from peaks in the matter density field, and evidence from numerical simulations and other analyses suggests that the dense inner regions of these objects largely persist today. These halos…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-24 M. Sten Delos , Margie Bruff , Adrienne L. Erickcek

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…

Astrophysics · Physics 2016-08-30 Paolo Salucci

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…

Astrophysics · Physics 2007-05-23 P. Salucci , A. Borriello