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Related papers: The spherical collapse model with shell crossing

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Cosmological simulations of galaxy formation often rely on prescriptions for star formation and feedback that depend on halo properties such as halo mass, central over-density, and virial temperature. In this paper we address the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 M. Trenti , B. D. Smith , E. J. Hallman , S. W. Skillman , J. M. Shull

Dark matter halos are typically defined as spheres that enclose some overdensity, but these sharp, somewhat arbitrary boundaries introduce non-physical artifacts such as backsplash halos, pseudo-evolution, and an incomplete accounting of…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-21 Ze'ev Vladimir , Calvin Osinga , Benedikt Diemer , Edgar M. Salazar , Eduardo Rozo

We investigate the evolution of dark matter halo shapes in cosmological N-body simulations both in scale free Einstein-De Sitter (EdS) and $\Lambda$CDM cosmologies. We compute the axis ratios ($q=b/a,s=c/a$) of well resolved central halos…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-03 Ayan Nanda , Nishikanta Khandai , J. S. Bagla , Swati Gavas

The relativistic time evolution of multi-layer spherically symmetric shell systems---consisting of infinitely thin shells separated by vacuum regions---is examined. Whenever two shells collide the evolution is continued with the assumption…

General Relativity and Quantum Cosmology · Physics 2011-04-13 Merse E. Gaspar , Istvan Racz

We follow the spin vector evolutions of well resolved dark matter haloes (containing more than 300 particles) in merger tree main branches from the Millennium and Millennium-II N-body simulations, from z about 3.3 to z = 0. We find that…

Astrophysics of Galaxies · Physics 2025-05-06 Jun Hou , Zhijian Luo , Cedric G. Lacey

Various laboratory-based experiments are underway attempting to detect dark matter directly. The event rates and detailed signals expected in these experiments depend on the dark matter phase space distribution on sub-milliparsec scales.…

Astrophysics · Physics 2011-08-31 Daniele S. M. Fantin , Michael R. Merrifield , Anne M. Green

We study the spherical collapse model for several dark energy scenarios using the fully nonlinear differential equation for the evolution of the density contrast within homogeneous spherical overdensities derived from Newtonian…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 F. Pace , J. -C. Waizmann , M. Bartelmann

We study the gravitational clustering of spherically symmetric overdensities and the statistics of the resulting dark matter halos in the "symmetron model", in which a new long range force is mediated by a $Z_2$ symmetric scalar field.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Laura Taddei , Riccardo Catena , Massimo Pietroni

Within the Halo Model of large scale structure, all matter is contained in dark matter halos. This simple yet powerful framework has been broadly applied to multiple data sets and enriched our comprehension of how matter is distributed in…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-25 Rodrigo Voivodic , Henrique Rubira , Marcos Lima

Structure formation provides a strong test of any cosmic acceleration model because a successful dark energy model must not inhibit {\black or overpredict} the development of observed large-scale structures. Traditional approaches to…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-28 C. Prescod-Weinstein , N. Afshordi

We derive the density profile for collisionless dissipationless dark matter haloes in hierarchical cosmologies making use of the Secondary Infall (SI) model. The novelties are: i) we deal with triaxial virialised objects; ii) their seeds in…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-10 Eduard Salvador-Solé , Jordi Viñas , Alberto Manrique , Sinue Serra

We investigate the structure of the dark matter halo formed in the cold dark matter scenario using $N$-body simulations. We simulated 12 halos with the mass of $6.6\times 10^{11}M_{\odot}$ to $8.0\times 10^{14}M_{\odot}$. In almost all…

Astrophysics · Physics 2008-11-26 Toshiyuki Fukushige , Junichiro Makino

We investigate the relationship between a dark matter halo's mass profile and measures of the velocity dispersion of kinematic tracers within its gravitational potential. By predicting the scaling relation of the halo mass with the aperture…

Astrophysics of Galaxies · Physics 2024-03-13 Andrew Sullivan , Chris Power , Connor Bottrell

In this work we investigate the spherical collapse model in flat FRW dark energy universes. We consider the Holographic Dark Energy (HDE) model as a dynamical dark energy scenario with a slowly time-varying equation-of-state (EoS) parameter…

General Relativity and Quantum Cosmology · Physics 2015-01-27 Tayebe Naderi , Mohammad Malekjani , Francesco Pace

The galaxy distribution in dark matter-dominated halos is expected to approximately trace the details of the underlying dark matter substructure. In this paper we introduce halo `core-tracking' as a way to efficiently follow the small-scale…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-19 Danila Korytov , Esteban Rangel , Lindsey Bleem , Nicholas Frontiere , Salman Habib , Katrin Heitmann , Joseph Hollowed , Adrian Pope

In this article we compare the halo mass function predicted by the excursion set theory with a drifting diffusive barrier against the results of N-body simulations for several cosmological models. This includes the standard LCDM case for a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 I. Achitouv , C. Wagner , J. Weller , Y. Rasera

The shapes of dark halos (e.g. spherical, oblate or triaxial) provide important clues to the formation history of the halos, to their baryon content and to the nature of the dark matter. The halo shapes also influence the dynamics of the…

Astrophysics · Physics 2016-08-30 Hans-Walter Rix , Max-Planck- Inst. fuer Astrophysik

We use two cosmological simulations of structure formation in the LambdaCDM scenario to study the evolutionary histories of dark-matter haloes and to characterize the Lagrangian regions from which they form. We focus on haloes identified at…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Mikolaj Borzyszkowski , Aaron D. Ludlow , Cristiano Porciani

Dark matter subhaloes are key for the predictions of simulations of structure formation, but their existence frequently ends prematurely due to two technical issues, namely numerical disruption in N-body simulations and halo finders failing…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-03 Benedikt Diemer , Peter Behroozi , Philip Mansfield

The evolution of large-scale structure within the standard model of cosmology is well posed only up to the onset of shell crossing, where particle trajectories appear to intersect. Beyond this point, the evolution equations become…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-04 Obinna Umeh
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