English
Related papers

Related papers: Halo Tracing with Atomic Hydrogen

200 papers

We present a study of the shapes, orientations, and alignments of Galactic dark matter subhalos in the ``Via Lactea'' simulation of a Milky Way-size LCDM host halo. Whereas isolated dark matter halos tend to be prolate, subhalos are…

Astrophysics · Physics 2009-11-13 M. Kuhlen , J. Diemand , P. Madau

Accurate knowledge of the morphology of halos and its evolution are key constraints on the galaxy formation model as well as a determinant parameter of the strong-lensing phenomenon. Using the cosmological hydrodynamic simulation, the…

Astrophysics of Galaxies · Physics 2023-01-25 Q. Petit , C. Ducourant , E. Slezak , D. Sluse , L. Delchambre

We investigate how galactic disk structures connect to the detailed properties of their host dark-matter halos using the TNG50 simulation. From the hydrodynamic and matched dark-matter-only runs, we measure a comprehensive list of halo…

Astrophysics of Galaxies · Physics 2026-03-20 Jinning Liang , Fangzhou Jiang , Houjun Mo , Andrew Benson , Philip F. Hopkins , Avishal Dekel , Luis C. Ho

Axion physics is briefly reviewed. Constraints from laboratory searches, astrophysics and cosmology require the axion mass to be in the range $10^{-6} \lesssim m_a < 3\cdot 10^{-3}$eV. Near the lower end of this range, axions are all or a…

High Energy Physics - Phenomenology · Physics 2017-08-23 P. Sikivie

The shape and orientation of dark matter (DM) halos are sensitive to the micro-physics of the DM particle, yet in many mass models, the symmetry axes of the Milky Way's DM halo are often assumed to be aligned with the symmetry axes of the…

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

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…

A standard paradigm is now available for the recent evolution (z < 10) of structure on galactic and larger scales. Most of the matter is assumed to be dark and dissipationless and to cluster hierarchically from gaussian initial conditions.…

Astrophysics · Physics 2007-05-23 Simon D. M. White

The results of numerical simulations of the dynamics of galactic disks, which are submerged into nonaxisymmetric dark massive halo are discussed. Galaxy disks dynamics in the nonaxisymmetric (triaxial) dark halo were investigated in detail…

Cosmology and Nongalactic Astrophysics · Physics 2010-07-15 Alexander Khoperskov , Mikhail Eremin , Sergej Khoperskov , Marija Butenko , Sergej Khrapov

Intrinsic alignments of galaxies are a significant astrophysical systematic affecting cosmological constraints from weak gravitational lensing. Obtaining numerical predictions from hydrodynamical simulations of expected survey volumes is…

We consider simple hydrodynamical models of galactic dark matter in which the galactic halo is a self-gravitating and self-interacting gas that dominates the dynamics of the galaxy. Modeling this halo as a sphericaly symmetric and static…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Luis G. Cabral-Rosetti , Tonatiuh Matos , Dario Nuñez , Roberto A. Sussman

This is the third paper in a series in which we attempt to put constraints on the flattening of dark halos in disk galaxies. For this purpose we need to analyse the observed XV diagrams in edge-on galaxies to accurately measure the radial…

Astrophysics of Galaxies · Physics 2015-05-18 J. C. O'Brien , K. C. Freeman , P. C. van der Kruit

I present an analysis of the density shapes of dark matter halos in LCDM and LWDM cosmologies. The main results are derived from a statistical sample of galaxy-mass halos drawn from a high resolution LCDM N-body simulation. Halo shapes show…

Astrophysics · Physics 2017-08-23 James S. Bullock

Several observational lines of evidence imply that a fraction of the dark matter in the Galaxy may be comprised of small cold clouds of molecular hydrogen. Such objects are difficult to detect because of their small size and low…

High Energy Astrophysical Phenomena · Physics 2025-01-28 A. V. Popkova , M. S. Pshirkov , A. V. Tuntsov

We study the three-dimensional and projected shapes of galaxy groups in the Sloan Digital Sky Survey Data Release 4, and examine the alignment between the orientation of the central galaxy and the spatial distribution of satellite galaxies.…

Astrophysics · Physics 2008-04-09 Yougang Wang , Xiaohu Yang , H. J. Mo , Cheng Li , Frank C. van den Bosch , Zuhui Fan , Xuelei Chen

We consider simple hydrodynamical models of galactic dark matter in which the galactic halo is a self-gravitating and self-interacting gas that dominates the dynamics of the galaxy. Modeling this halo as a sphericaly symmetric and static…

High Energy Physics - Phenomenology · Physics 2007-05-23 Luis G. Cabral-Rosetti , Dario Nunez , Roberto A. Sussman , Tonatiuh Matos

We introduce the flattening equation, which relates the shape of the dark halo to the angular velocity dispersions and the density of a tracer population of stars. It assumes spherical alignment of the velocity dispersion tensor, as seen in…

Astrophysics of Galaxies · Physics 2016-05-25 A. Bowden , N. W. Evans , A. A. Williams

In a previous paper (Paper I) a method was developed to determine the shapes of dark matter halos of spiral galaxies from the flaring and velocity dispersion of the gas layer. Here I present the results for the almost edge-on Scd galaxy NGC…

Astrophysics · Physics 2007-05-23 Rob P. Olling

We examine the properties of dark matter halos within a rich galaxy cluster using a high resolution simulation that captures the cosmological context of a cold dark matter universe. The mass and force resolution permit the resolution of 150…

Astrophysics · Physics 2009-10-30 Sebastiano Ghigna , Ben Moore , Fabio Governato , George Lake , Thomas Quinn , Joachim Stadel

We use a cosmological simulation of the Local Group to make quantitative and speculative predictions for direct detection experiments. Cold dark matter (CDM) halos form via a complex series of mergers, accretion events and violent…