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Related papers: Predicting the density profiles of the first halos

200 papers

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 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

Throughout cosmological simulations, the properties of the matter density field in the initial conditions have a decisive impact on the features of the structures formed today. In this paper we use a random-forest classification algorithm…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-20 Jazhiel Chacón , J. Alberto Vázquez , Erick Almaraz

Spherical density profiles and specific angular momentum profiles of Dark Matter halos found in cosmological N-body simulations have been measured extensively. The distribution of the total angular momentum of dark matter halos is also used…

Astrophysics · Physics 2017-08-23 Tom Abel , Rupert C. Croft , Lars Hernquist

High resolution N-body simulations have all but converged on a common empirical form for the shape of the density profiles of halos, but the full understanding of the underlying physics of halo formation has eluded them so far. We…

We consider three cosmological models with non-power-law spectra of primordial density perturbations and test them against $\Lambda$CDM in density profiles of dark matter halos. We found that, despite the significant difference in initial…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-13 M. V. Tkachev , S. V. Pilipenko , E. V. Mikheeva , V. N. Lukash

Halos of similar mass and redshift exhibit a large degree of variability in their differential properties, such as dark matter, hot gas, and stellar mass density profiles. This variability is an indicator of diversity in the formation…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-20 Arya Farahi , Daisuke Nagai , Dhayaa Anbajagane

The simple, conventional dark matter halo mass definitions commonly used in cosmological simulations ("virial" mass, FoF mass, $M_{50,100,200,...}$) only capture part of the collapsed material and are therefore inconsistent with the halo…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-14 Donnino Anderhalden , Juerg Diemand

In the standard cosmological model a mysterious cold dark matter (CDM) component dominates the formation of structures. Numerical studies of the formation of CDM halos have produced several robust results that allow unique tests of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Jürg Diemand , Ben Moore

Halo Abundance Matching has been used to construct a one-parameter mapping between galaxies and dark matter haloes by assuming that halo mass and galaxy luminosity (or stellar mass) are monotonically related. While this approach has been…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-19 Andrea Kulier , Jeremiah P. Ostriker

Dark-matter halos are the scaffolding around which galaxies and clusters are built. They form when the gravitational instability of primordial density fluctuations causes regions which are denser than average to slow their cosmic expansion,…

Astrophysics · Physics 2007-05-23 Paul R. Shapiro , Ilian T. Iliev , Hugo Martel , Kyungjin Ahn , Marcelo A. Alvarez

Many independent high-resolution simulations of structure formation in cold dark matter models show that galactic halos should have singular core profiles. This is in stark contrast with observations of both low- and high-surface brightness…

Astrophysics · Physics 2007-05-23 Steen Hannestad

We calculate the density profiles of virialized halos in the case of structure evolving hierarchically from a scale-free Gaussian delta-field having a power spectrum $P(k)\propto k^n$ in a Omega=1 Universe; we suppose that the initial…

Astrophysics · Physics 2007-05-23 A. Del Popolo , M. Gambera

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

In our modern understanding of galaxy formation, every galaxy forms within a dark matter halo. The formation and growth of galaxies over time is connected to the growth of the halos in which they form. The advent of large galaxy surveys as…

Astrophysics of Galaxies · Physics 2018-10-17 Risa H. Wechsler , Jeremy L. Tinker

I develop a model for the abundance and spatial distribution of dark matter subclumps. The model shows that subclumps of massive parent halos formed at earlier times than subclumps of the same mass in lower mass parents; equivalently, halos…

Astrophysics · Physics 2009-11-07 Ravi K. Sheth

We describe the first results from two observational projects aimed at measuring the amount and spatial distribution of dark matter in distant early-type galaxies (E/S0s) and clusters of galaxies. At the galaxy scale, the Lenses Structure…

Astrophysics · Physics 2007-05-23 T. Treu , L. V. E. Koopmans , D. J. Sand , G. P. Smith , R. S. Ellis

The size and time of formation of the first gravitationally bound objects in the Universe is set by the microphysical properties of the dark matter. It is argued that observations seem to favour cold and thermal candidates for the main…

Astrophysics · Physics 2016-11-09 Dominik J. Schwarz

We use explainable neural networks to connect the evolutionary history of dark matter halos with their density profiles. The network captures independent factors of variation in the density profiles within a low-dimensional representation,…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-22 Luisa Lucie-Smith , Hiranya V. Peiris , Andrew Pontzen

The Universe was nearly smooth and homogeneous before a redshift of z = 100, about 20 million years after the Big Bang. After this epoch, the tiny fluctuations imprinted upon the matter distribution during the initial expansion began to…

Astrophysics · Physics 2009-11-10 Juerg Diemand , Ben Moore , Joachim Stadel
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