A Study of the Properties and Dynamics of the Disk of Satellites in a Milky-Way-like Galaxy System

Abstract

The dynamics of the satellite systems of Milky-Way-like galaxies offer a useful means by which to study the galaxy formation process in the cosmological context. It has been suggested that the currently observed anisotropic distribution of the satellites in such galaxy systems is inconsistent with the concordance $\Lambda CDM$ cosmology model on the galactic scale if the observed satellites are random samples of the dark matter (DM) sub-halos that are nearly isotropically distributed around the central galaxy. In this study, we present original high-resolution zoom-in studies of central galaxies and satellite systems based upon initial conditions for the DM distribution from the Aquarius simulations but with substantial high-resolution baryon physics added. We find that the galaxy most like the Milky Way in this study does indeed contain a disk of satellites (DOS). Although one galaxy DOS system does not answer the question of how common such disks are, it does allow the opportunity to explore the properties and dynamics of the DOS system. Our investigation centers on the spatial arrangement (distances, angles, etc.) of satellites in this Milky-Way-like galaxy system with a specific emphasis on identifying and analyzing the disk-like structure along with its dynamical and morphological properties. Among the conclusions from this study, we find that the satellites and DM sub-halos in the galaxy simulations are anisotropically distributed. The dynamical properties of the satellites, however, indicate that the direction of the angular momentum vector of the whole satellite system is different from the normal direction of the fitted DOS and from the normal direction of the velocity dispersion of the system. Hence, the fitted DOS appears to be comprised of infalling sub-halos and is not a rotationally supported system.

arXiv comment22 pages, 14 figures

References in corpus (73)

• The cosmological simulation code GADGET-2
• Dark Matter Substructure in Galactic Halos
• Where are the missing galactic satellites?
• Populating a cluster of galaxies - I. Results at z=0
• The Aquarius Project: the subhalos of galactic halos
• The Kinematics of the Ultra-Faint Milky Way Satellites: Solving the Missing Satellite Problem
• The Faintest Dwarf Galaxies
• The great disk of Milky-Way satellites and cosmological sub-structures
• The formation of disc galaxies in high resolution moving-mesh cosmological simulations
• The VPOS: a vast polar structure of satellite galaxies, globular clusters and streams around the Milky Way
• The Anisotropic Distribution of Galactic Satellites
• The Formation and Survival of Discs in a Lambda-CDM Universe
• A Complete Spectroscopic Survey of the Milky Way Satellite Segue 1: The Darkest Galaxy
• The Distribution of Satellite Galaxies: The Great Pancake
• The dark matter crisis: falsification of the current standard model of cosmology
• Local-Group tests of dark-matter Concordance Cosmology: Towards a new paradigm for structure formation
• The spatial distribution of the Milky Way and Andromeda satellite galaxies
• PAndAS' progeny: extending the M31 dwarf galaxy cabal
• The orbital poles of Milky Way satellite galaxies: a rotationally supported disc-of-satellites
• Anisotropic Distribution of SDSS Satellite Galaxies: Planar (not Polar) Alignment
• PAndAS' cubs: discovery of two new dwarf galaxies in the surroundings of the Andromeda and Triangulum galaxies
• Overview of the DESI Milky Way Survey
• The population of Milky Way satellites in the LambdaCDM cosmology
• Do dwarf galaxies form in tidal tails?
• Public data release of the FIRE-2 cosmological zoom-in simulations of galaxy formation
• The Hestia project: simulations of the Local Group
• Mismatch and Misalignment: Dark Haloes and Satellites of Disc Galaxies
• Dwarf Spheroidal Satellite Galaxies Without Dark Matter: Results From Two Different Numerical Techniques
• The Anisotropic Distribution of M 31 Satellite Galaxies: A Polar Great Plane of Early-Type Companions
• The satellite distribution of M31
• The Milky Way's Disk of Classical Satellite Galaxies in Light of Gaia DR2
• Does M31 result from an ancient major merger?
• Anisotropy in the distribution of satellites around primary galaxies in the 2dFGRS: the Holmberg effect
• The Cross-Correlation between Galaxies and Groups: Probing the Galaxy Distribution in and around Dark Matter Haloes
• Discs of Satellites: the new dwarf spheroidals
• Satellite Systems around Galaxies in Hydrodynamic Simulations
• Dwarf galaxy formation induced by galaxy interactions
• Anisotropies in the Distribution of Satellite Galaxies
• The Link between Galactic Satellite Orbits and Subhalo Accretion
• Dwarf-spheroidal satellites: are they of tidal origin?
• Lacerta I and Cassiopeia III: Two luminous and distant Andromeda satellite dwarf galaxies found in the 3π Pan-STARRS1 survey
• Formation history, structure and dynamics of discs and spheroids in simulated Milky Way mass galaxies
• Are Great Disks Defined by Satellite Galaxies in Milky-Way Type Halos Rare in $\Lambda$CDM model?
• Making Counter-Orbiting Tidal Debris: The Origin of the Milky Way Disc of Satellites
• How common is the Milky Way - satellite system alignment?
• Anisotropic Locations of Satellite Galaxies: Clues to the Orientations of Galaxies within their Dark Matter Halos
• Planes of satellites around Milky Way/M31-mass galaxies in the FIRE simulations and comparisons with the Local Group
• The Spatial Distribution of Galactic Satellites in the LCDM Cosmology
• Angular distribution of satellite galaxies from the Sloan Digital Sky Survey Data Release 4
• The Anisotropic Distribution of Satellite Galaxies
• Can filamentary accretion explain the orbital poles of the Milky Way satellites?
• The effect of the LMC on the Milky Way system
• Does the dwarf galaxy system of the Milky Way originate from Andromeda?
• The Structure of the Outer Halo of the Galaxy and its Relationship to Nearby Large-Scale Structure
• Local Group Dwarf Galaxies: Nature And Nurture
• A new spin on disks of satellite galaxies
• Evolution of galactic planes of satellites in the EAGLE simulation
• Dwarf spheroidal satellites of the Milky Way from dark matter free tidal dwarf galaxy progenitors: maps of orbits
• The Distribution of Satellite Galaxies in a Lambda-CDM Universe
• The globular cluster system of the Milky Way: accretion in a cosmological context
• The lopsided distribution of satellite galaxies
• The tangential velocity excess of the Milky Way satellites
• Tidal Dwarf Galaxies and missing baryons
• Distribution of satellite galaxies in high redshift groups
• On the Co-Orbitation of Satellite Galaxies Along the Great Plane of Andromeda: NGC 147, NGC 185, and Expectations from Cosmological Simulations
• Could the Magellanic Clouds be tidal dwarves expelled from a past-merger event occurring in Andromeda?
• Alignment between Luminous Red Galaxies and surrounding structures at $z\sim 0.5$
• Satellite mass functions and the faint end of the galaxy mass-halo mass relation in LCDM
• Planes of satellites around simulated disc galaxies: I.- Finding high-quality planar configurations from positional information and their comparison to MW/M31 data
• Spatial and orbital planes of the Milky Way satellites: unusual but consistent with $\Lambda$CDM
• Is there a disk of satellites around the Milky Way?
• Anisotropic satellite accretion onto the Local Group with HESTIA
• Constraints on the angular distribution of satellite galaxies about spiral hosts