English
Related papers

Related papers: VOBOZ: An Almost-Parameter-Free Halo-Finding Algor…

200 papers

ZOBOV (ZOnes Bordering On Voidness) is an algorithm that finds density depressions in a set of points, without any free parameters, or assumptions about shape. It uses the Voronoi tessellation to estimate densities, which it uses to find…

Astrophysics · Physics 2008-05-15 Mark C. Neyrinck

We have developed a new halo finding method, Physically Self-Bound (PSB) group finding algorithm, which can efficiently identify halos located even at crowded regions. This method combines two physical criteria such as the tidal radius of a…

Astrophysics · Physics 2009-11-10 Juhan Kim , Changbom Park

We describe a new algorithm for finding substructures within dark matter haloes from N-body simulations. The algorithm relies upon the fact that dynamically distinct substructures in a halo will have a {\em local} velocity distribution that…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-27 Pascal J. Elahi , Robert J. Thacker , Lawrence M. Widrow

Any measurement made using an N-body simulation is subject to noise due to the finite number of particles used to sample the dark matter distribution function, and the lack of structure below the simulation resolution. This noise can be…

Astrophysics of Galaxies · Physics 2017-08-16 Andrew J. Benson

We present an algorithm which is designed to allow the efficient identification and preliminary dynamical analysis of thousands of structures and substructures in large N-body simulations. First we utilise a refined density gradient system…

Astrophysics · Physics 2009-11-10 Jochen Weller , Jeremiah P Ostriker , Paul Bode , Laurie Shaw

We use a set of large cosmological N-body simulations to study the internal structure of dark matter haloes which form in scale-free models. We find that the radius r_178 corresponding to a mean interior overdensity of 178 accurately…

Astrophysics · Physics 2015-06-24 Shaun Cole , Cedric Lacey

We present "sheet+release" simulations that reliably follow the evolution of dark matter structure at and below the dark matter free-streaming scale, where instabilities in traditional N-body simulations create a large population of…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-03 Jens Stücker , Raul E. Angulo , Oliver Hahn , Simon D. M. White

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

We introduce a new method to calculate dark matter halo density profiles from simulations. Each particle is 'smeared' over its orbit to obtain a dynamical profile that is averaged over a dynamical time, in contrast to the traditional…

Astrophysics of Galaxies · Physics 2024-01-26 Claudia Muni , Andrew Pontzen , Jason L. Sanders , Martin P. Rey , Justin I. Read , Oscar Agertz

[abridged] We present a detailed comparison of fundamental dark matter halo properties retrieved by a substantial number of different halo finders. These codes span a wide range of techniques including friends-of-friends (FOF),…

We use an extremely large volume ($2.4h^{-3}{\rm Gpc}^{3}$), high resolution N-body simulation to measure the higher order clustering of dark matter haloes as a function of mass and internal structure. As a result of the large simulation…

Astrophysics · Physics 2008-07-31 R. E. Angulo , C. M. Baugh , C. G. Lacey

This work explores the ability of computer vision algorithms to characterise dark matter haloes formed in different models of structure formation. We produce surface mass density maps of the most massive haloes in a suite of eight numerical…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-19 Julian Merten , Quim Llorens , Hans Winther

We present a deep-learning-based approach for identifying dark matter haloes in cosmological N-body simulations. Our framework consists of a volumetric Convolutional Neural Network to classify individual simulation particles as either halo…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-26 Soumadeep Maiti , Carlos M. Correa , Andrea Fiorilli , Andrés N. Ruiz , Dante J. Paz , Alejandro Pérez Fernández , Ariel G. Sánchez

This paper introduces a new approach toward characterizing local structural features of two-dimensional particle systems. The approach can accurately identify and characterize defects in high-temperature crystals, distinguish a wide range…

Materials Science · Physics 2024-11-14 Emanuel A. Lazar , Jiayin Lu , Chris H. Rycroft , Deborah Schwarcz

High-resolution cosmological N-body simulations are excellent tools for modelling the formation and clustering of dark matter haloes. These simulations suggest complex physical theories of halo formation governed by a set of effective…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-24 Androniki Dimitriou , Christoph Weniger , Camila A. Correa

Feedback processes from baryons are expected to strongly affect weak-lensing observables of current and future cosmological surveys. In this paper we present a new parametrisation of halo profiles based on gas, stellar, and dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-02 Aurel Schneider , Romain Teyssier , Joachim Stadel , Nora Elisa Chisari , Amandine M. C. Le Brun , Adam Amara , Alexandre Refregier

We study how well void-finding algorithms identify cosmic void regions and whether we can quantitatively and qualitatively compare the voids they find with dynamical information from the underlying matter distribution. Using the ORIGAMI…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-07 Dahlia Veyrat , Kelly A. Douglass , Segev BenZvi

The goal of learning to hash (L2H) is to derive data-dependent hash functions from a given data distribution in order to map data from the input space to a binary coding space. Despite the success of L2H, two observations have cast doubt on…

Information Retrieval · Computer Science 2025-08-05 Yang Xu , Kai Ming Ting

In many data analysis applications the following scenario is commonplace: we are given a point set that is supposed to sample a hidden ground truth $K$ in a metric space, but it got corrupted with noise so that some of the data points lie…

Computational Geometry · Computer Science 2017-03-28 Mickaël Buchet , Tamal K. Dey , Jiayuan Wang , Yusu Wang

We use group size haloes identified with a ``friends of friends'' (FOF) algorithm in a concordance $\Lambda \rm{CDM}$ GADGET2 (dark matter only) simulation to investigate the dependence of halo properties on the environment at $z=0$. The…

Astrophysics · Physics 2008-11-26 Cinthia Ragone-Figueroa , Manolis Plionis
‹ Prev 1 2 3 10 Next ›