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Related papers: Predicting the density profiles of the first halos

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We describe a new scenario for the formation of primordial black holes (PBHs). In the early Universe, the long-range forces mediated by the scalar fields can lead to formation of halos of heavy particles even during the radiation-dominated…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-28 Marcos M. Flores , Alexander Kusenko

We recently showed that postulated ultracompact minihalos with a steep density profile do not form in realistic simulations with enhanced initial perturbations. In this paper we assume that a small fraction of the dark matter consists of…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-16 Julian Adamek , Christian T. Byrnes , Mateja Gosenca , Shaun Hotchkiss

The first generation of haloes forms from the collapse of the smallest peaks in the initial density field. $N$-body simulations of this process suggest a prompt formation of a steep power-law cusp, but these calculations are plagued by…

Astrophysics of Galaxies · Physics 2023-09-13 Lurdes Ondaro-Mallea , Raul E. Angulo , Jens Stücker , Oliver Hahn , Simon D. M. White

Adaptive SPH and N-body simulations were carried out to study the evolution of the equilibrium structure of dark matter halos that result from the gravitational instability and fragmentation of cosmological pancakes. Such halos resemble…

Astrophysics · Physics 2009-11-06 Marcelo Alvarez , Paul R. Shapiro , Hugo Martel

We explore the clustering properties of high redshift dark matter halos, focusing on halos massive enough to host early generations of stars or galaxies at redshift 10 and greater. Halos are extracted from an array of dark matter…

Astrophysics · Physics 2009-11-13 Darren S. Reed , Richard Bower , Carlos S. Frenk , Adrian Jenkins , Tom Theuns

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 Ilian T. Iliev , Paul R. Shapiro

In this proceeding, we briefly review three recent results. First, we show that halos formed in simulations with gas cooling are significantly rounder than halos formed in dissipationless $N$-body simulations. The increase in principle axis…

Astrophysics · Physics 2016-11-03 Andrew R. Zentner , Savvas M. Koushiappas , Stelios Kazantzidis

Adaptive SPH and N-body simulations were carried out to study the collapse and evolution of dark matter halos that result from the gravitational instability and fragmentation of cosmological pancakes. Such halos resemble those formed by…

Astrophysics · Physics 2007-05-23 Marcelo A. Alvarez , Paul R. Shapiro , Hugo Martel

We investigate the structure of cold dark matter halos using advanced models of spherical collapse and accretion in an expanding Universe. These base on solving time-dependent equations for the moments of the phase-space distribution…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 A. Lapi , A. Cavaliere

We obtain predictions for the properties of cold dark matter annihilation radiation using high resolution hydrodynamic zoom-in cosmological simulations of Milky Way-like galaxies (APOSTLE project) carried out as part of the "Evolution and…

Earth-mass dark matter microhalos with size of ~100 AUs are the first structures formed in the universe, if the dark matter of the Universe are made of neutralino. Here, we report the results of ultra-high-resolution simulations of the…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-09 Tomoaki Ishiyama , Junichiro Makino , Toshikazu Ebisuzaki

Cold dark matter (CDM) could be composed of primordial black holes (PBH) in addition to or instead of more orthodox weakly interacting massive particle dark matter (PDM). We study the formation of the first structures in such $\Lambda$PBH…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-23 Derek Inman , Yacine Ali-Haïmoud

We simulate neutralino dark matter ($\chi$DM) haloes from their initial collapse, at $\sim$ earth mass, up to a few percent solar. Our results confirm that the density profiles of the first haloes are described by a $\sim r^{-1.5}$…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-06 Raul E. Angulo , Oliver Hahn , Aaron Ludlow , Silvia Bonoli

The mass distribution of dark matter haloes is the result of the hierarchical growth of initial density perturbations through mass accretion and mergers. We use an interpretable machine-learning framework to provide physical insights into…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-06 Luisa Lucie-Smith , Susmita Adhikari , Risa H. Wechsler

Dark matter haloes play a fundamental role in cosmological structure formation. The most common approach to model their assembly mechanisms is through N-body simulations. In this work we present an innovative pathway to predict dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-15 Mauro Bernardini , Lucio Mayer , Darren Reed , Robert Feldmann

We investigate the collapse and internal structure of dark matter halos. We consider halo formation from initially scale-free perturbations, for which gravitational collapse is self-similar. Fillmore and Goldreich (1984) and Bertschinger…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-21 Yoram Lithwick , Neal Dalal

We argue that primordial dark matter halos could be generated during radiation domination by long range attractive forces stronger than gravity. In this paper we derive the conditions under which these structures could dominate the dark…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-17 Stefano Savastano , Luca Amendola , Javier Rubio , Christof Wetterich

Motivated by the recent direct detection of cosmological gas infall, we develop an analytical model for calculating the mean density profile around an initial overdensity that later forms a dark matter halo. We account for the problem of…

Astrophysics · Physics 2009-11-07 Rennan Barkana

We discuss various aspects of the inner structure formation in virialized dark matter (DM) halos that form as primordial density inhomogeneities evolve in the cosmological standard model. The main focus is on the study of central…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-04 A. G. Doroshkevich , V. N. Lukash , E. V. Mikheeva

We study the structure and evolution of dark matter halos from z = 300 to z = 6 for two cosmological N-body simulation initialization techniques. While the second order Lagrangian perturbation theory (2LPT) and the Zel'dovich approximation…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-17 Daniel J. Sissom , Kelly Holley-Bockelmann , Manodeep Sinha