English
Related papers

Related papers: Multi-Dimensional Density Estimation and Phase Spa…

200 papers

Velocity dispersions have been employed as a method to measure masses of clusters. To complement this conventional method, we explore the possibility of constraining cluster masses from the stacked phase space distribution of galaxies at…

Astrophysics of Galaxies · Physics 2019-09-04 Akinari Hamabata , Masamune Oguri , Takahiro Nishimichi

Massive neutrinos suppress the growth of cosmic structure on nonlinear scales, motivating the use of information beyond the power spectrum to tighten constraints on the neutrino mass, for example by considering cosmic voids. It was recently…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-03 Adrian E. Bayer , Jia Liu , Christina D. Kreisch , Alice Pisani

We present a new high-resolution N-body algorithm for cosmological simulations. The algorithm employs a traditional particle-mesh technique on a cubic grid and successive multilevel relaxations on the finer meshes, introduced recursively in…

Astrophysics · Physics 2009-10-30 Andrey V. Kravtsov , Anatoly A. Klypin , Alexei M. Khokhlov

Shape measurements of galaxies and galaxy clusters are widespread in the analysis of cosmological simulations. But the limitations of those measurements have been poorly investigated. In this paper, we explain why the quality of the shape…

Astrophysics of Galaxies · Physics 2023-02-22 Moritz S. Fischer , Lucas M. Valenzuela

We study the distribution function (DF) of dark matter particles in haloes of mass range 10^{14}--10^{15}\Msun. In the numerical part of this work we measure the DF for a sample of relaxed haloes formed in the simulation of a standard…

Mass estimators are a key tool to infer the dark matter content in pressure-supported systems like dwarf spheroidal galaxies (dSphs). We construct an estimator for enclosed masses based on the virial theorem which is insensitive to…

Astrophysics of Galaxies · Physics 2018-09-26 Raphaël Errani , Jorge Peñarrubia , Matthew G. Walker

The partial spatial separation of cold dark matter (DM) and gas is a ubiquitous feature in the formation of cosmic large-scale structure. This separation, termed dissociation, is prominent in galaxy clusters that formed through collisions…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-07 William McDonald , Danail Obreschkow , Lilian Garratt-Smithson

N-body simulations suggest that the substructures that survive inside dark matter haloes follow universal distributions in mass and radial number density. We demonstrate that a simple analytical model can explain these subhalo distributions…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-17 Jiaxin Han , Shaun Cole , Carlos S. Frenk , Yipeng Jing

We study the relation between the halo and matter density fields -- commonly termed bias -- in the LCDM framework. In particular, we examine the local model of biasing at quadratic order in the matter density. This model is characterized by…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Jennifer E. Pollack , Robert E. Smith , Cristiano Porciani

We develop a simple analytic model for the gravitational clustering of dark matter haloes to understand how their spatial distribution is biased relative to that of the mass. The statistical distribution of dark haloes within the initial…

Astrophysics · Physics 2015-06-24 H. J. Mo , S. D. M. White

In the present work we study the statistics of haloes, which in the halo model determines the distribution of galaxies. Haloes are known to be biased tracer of dark matter, and at large scales it is usually assumed there is no intrinsic…

Astrophysics · Physics 2015-05-13 Silvia Bonoli , Ue-Li Pen

Starting from a very accurate model for density-in-cells statistics of dark matter based on large deviation theory, a bias model for the tracer density in spheres is formulated. It adopts a mean bias relation based on a quadratic bias model…

We develop a method of multifractal analysis of N-body cosmological simulations that improves on the customary counts-in-cells method by taking special care of the effects of discreteness and large scale homogeneity. The analysis of the…

Astrophysics · Physics 2015-03-13 Jose Gaite

We use a high resolution $\Lambda$CDM numerical simulation to calculate the mass function of dark matter haloes down to the scale of dwarf galaxies, back to a redshift of fifteen, in a 50 $h^{-1}$Mpc volume containing 80 million particles.…

We provide new constraints on the dark matter halo density profile of Milky Way (MW) dwarf spheroidal galaxies (dSphs) using the phase-space distribution function (DF) method. After assessing the systematics of the approach against mock…

Astrophysics of Galaxies · Physics 2024-05-31 Kevin E. Andrade , Manoj Kaplinghat , Mauro Valli

We present a new method for calculating the merger history of matter halos in hierarchical clustering cosmologies. The linear density field is smoothed on a range of scales, these are then ordered in decreasing density and a merger tree…

Astrophysics · Physics 2015-06-24 Domingos D. C. Rodrigues , Peter A. Thomas

We present a scheme to extend the halo mass resolution of N-body simulations of the hierarchical clustering of dark matter. The method uses the density field of the simulation to predict the number of sub-resolution dark matter haloes…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Raul E. Angulo , Carlton M. Baugh , Carlos S. Frenk , Cedric G. Lacey

We propose a lightweight deep convolutional neural network (lCNN) to estimate cosmological parameters from simulated three-dimensional dark matter (DM) halo distributions and associated statistics. The training dataset comprises 2000…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-20 Zhiwei Min , Xu Xiao , Jiacheng Ding , Liang Xiao , Jie Jiang , Donglin Wu , Qiufan Lin , Yang Wang , Shuai Liu , Zhixin Chen , Xiangru Li , Jinqu Zhang , Le Zhang , Xiao-Dong Li

We study structure formation in the presence of primordial non-Gaussianity of the local type with parameters f_NL and g_NL. We show that the distribution of dark-matter halos is naturally described by a multivariate bias scheme where the…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-14 Tommaso Giannantonio , Cristiano Porciani

We use self-similarity in N-body simulations of scale-free models to test for resolution dependence in the mass function and two-point correlation functions of dark matter halos. We use 1024$^3$ particle simulations performed with ABACUS,…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-22 M. Leroy , L. Garrison , D. Eisenstein , M. Joyce , S. Maleubre