The multiplicity and anisotropy of galactic satellite accretion

Abstract

We study the incidence of group and filamentary dwarf galaxy accretion into Milky Way (MW) mass haloes using two types of hydrodynamical simulations: EAGLE, which resolves a large cosmological volume, and the AURIGA suite, which are very high resolution zoom-in simulations of individual MW-sized haloes. The present-day 11 most massive satellites are predominantly (75%) accreted in single events, 14% in pairs and 6% in triplets, with higher group multiplicities being unlikely. Group accretion becomes more common for fainter satellites, with 60% of the top 50 satellites accreted singly, 12% in pairs, and 28% in richer groups. A group similar in stellar mass to the Large Magellanic Cloud (LMC) would bring on average 15 members with stellar mass larger than $10^4{\mathrm{M}}_{\odot }$. Half of the top 11 satellites are accreted along the two richest filaments. The accretion of dwarf galaxies is highly anisotropic, taking place preferentially perpendicular to the halo minor axis, and, within this plane, preferentially along the halo major axis. The satellite entry points tend to be aligned with the present-day central galaxy disc and satellite plane, but to a lesser extent than with the halo shape. Dwarfs accreted in groups or along the richest filament have entry points that show an even larger degree of alignment with the host halo than the full satellite population. We also find that having most satellites accreted as a single group or along a single filament is unlikely to explain the MW disc of satellites.

arXiv comment15 pages, 17 figures. Minor changes. MNRAS in press

References in corpus (97)

• Planck 2013 results. XVI. Cosmological parameters
• The cosmological simulation code GADGET-2
• HEALPix -- a Framework for High Resolution Discretization, and Fast Analysis of Data Distributed on the Sphere
• Simulating the joint evolution of quasars, galaxies and their large-scale distribution
• The EAGLE project: Simulating the evolution and assembly of galaxies and their environments
• E pur si muove: Galiliean-invariant cosmological hydrodynamical simulations on a moving mesh
• The Aquarius Project: the subhalos of galactic halos
• The observed properties of dwarf galaxies in and around the Local Group
• GADGET: A code for collisionless and gasdynamical cosmological simulations
• The hierarchical formation of the brightest cluster galaxies
• The EAGLE simulations of galaxy formation: calibration of subgrid physics and model variations
• Substructures in hydrodynamical cluster simulations
• The subhalo populations of LCDM dark haloes
• The APOSTLE simulations: solutions to the Local Group's cosmic puzzles
• Eight New Milky Way Companions Discovered in First-Year Dark Energy Survey Data
• The Auriga Project: the properties and formation mechanisms of disc galaxies across cosmic time
• Beasts of the Southern Wild: Discovery of nine Ultra Faint satellites in the vicinity of the Magellanic Clouds
• Simulating galactic outflows with thermal supernova feedback
• Eight Ultra-faint Galaxy Candidates Discovered in Year Two of the Dark Energy Survey
• Dark Matter Halos within Clusters
• A Vast Thin Plane of Co-rotating Dwarf Galaxies Orbiting the Andromeda Galaxy
• The EAGLE simulations of galaxy formation: public release of halo and galaxy catalogues
• Third-Epoch Magellanic Cloud Proper Motions I: HST/WFC3 data and Orbit Implications
• Evolution of the cosmic web
• A General Class of Lagrangian Smoothed Particle Hydrodynamics Methods and Implications for Fluid Mixing Problems
• The great disk of Milky-Way satellites and cosmological sub-structures
• The VPOS: a vast polar structure of satellite galaxies, globular clusters and streams around the Milky Way
• The origin and implications of dark matter anisotropic cosmic infall on ~L* haloes
• The RAVE survey: the Galactic escape speed and the mass of the Milky Way
• The Anisotropic Distribution of Galactic Satellites
• The Distribution of Satellite Galaxies: The Great Pancake
• NEXUS: Tracing the Cosmic Web Connection
• Sagittarius II, Draco II and Laevens 3: three new Milky Way satellites discovered in the Pan-STARRS 1 3pi Survey
• The feeble giant. Discovery of a large and diffuse Milky Way dwarf galaxy in the constellation of Crater
• The EAGLE simulations of galaxy formation: the importance of the hydrodynamics scheme
• A timing constraint on the (total) mass of the Large Magellanic Cloud
• Quenching and ram pressure stripping of simulated Milky Way satellite galaxies
• The APOSTLE project: Local Group kinematic mass constraints and simulation candidate selection
• Bent by baryons: the low mass galaxy-halo relation
• A chronicle of galaxy mass assembly in the EAGLE simulation
• N-body Dark Matter Haloes with simple Hierarchical Histories
• The spin and orientation of dark matter halos within cosmic filaments
• Sweating the small stuff: simulating dwarf galaxies, ultra-faint dwarf galaxies, and their own tiny satellites
• Co-orbiting satellite galaxy structures are still in conflict with the distribution of primordial dwarf galaxies
• Infall of substructures onto a Milky Way-like dark halo
• A Magellanic Origin of the DES Dwarfs
• The Three-Dimensional Structure of the M31 Satellite System; Strong Evidence for an Inhomogeneous Distribution of Satellites
• The Shape of Dark Matter Haloes in the Aquarius Simulations: Evolution and Memory
• Hydra II: a faint and compact Milky Way dwarf galaxy found in the Survey of the Magellanic Stellar History
• Inferring the Andromeda Galaxy's mass from its giant southern stream with Bayesian simulation sampling
• Co-planar streams, pancakes, and angular-momentum exchange in high-z disc galaxies
• Horologium II: a Second Ultra-faint Milky Way Satellite in the Horologium Constellation
• Anisotropy in the Distribution of Satellite Galaxy Orbits
• The total satellite population of the Milky Way
• Dwarf Galaxies and the Cosmic Web
• The preferred direction of infalling satellite galaxies in the Local Group
• Shaken and Stirred: The Milky Way's Dark Substructures
• Mismatch and Misalignment: Dark Haloes and Satellites of Disc Galaxies
• The vast thin plane of M31 co-rotating dwarfs: an additional fossil signature of the M31 merger and of its considerable impact in the whole Local Group
• A Hero's Dark Horse: Discovery of an Ultra-Faint Milky Way Satellite in Pegasus
• The Fate of Substructures in Cold Dark Matter Haloes
• Estimating the dark matter halo mass of our Milky Way using dynamical tracers
• Satellites of LMC-Mass Dwarfs: Close Friendships Ruined by Milky Way Mass Halos
• Satellite Dwarf Galaxies in a Hierarchical Universe: The Prevalence of Dwarf-Dwarf Major Mergers
• Warps and waves in the stellar discs of the Auriga cosmological simulations
• Planes of satellite galaxies: when exceptions are the rule
• An Ultra-Faint Galaxy Candidate Discovered in Early Data from the Magellanic Satellites Survey
• Identifying true satellites of the Magellanic Clouds
• The alignment of satellite galaxies and cosmic filaments: observations and simulations
• Did the Milky Way dwarf satellites enter the halo as a group?
• The universal nature of subhalo accretion
• The Link between Galactic Satellite Orbits and Subhalo Accretion
• The predicted luminous satellite populations around SMC and LMC-mass galaxies - A missing satellite problem around the LMC?
• How common is the Milky Way - satellite system alignment?
• The Spatial Distribution of Galactic Satellites in the LCDM Cosmology
• The build up of the correlation between halo spin and the large scale structure
• Milky Way mass constraints from the Galactic satellite gap
• Dissecting the Evolution of Dark Matter Subhaloes in the Bolshoi Simulation
• Can filamentary accretion explain the orbital poles of the Milky Way satellites?
• Does the dwarf galaxy system of the Milky Way originate from Andromeda?
• Lessons from the Auriga discs: The hunt for the Milky Way's ex-situ disc is not yet over
• Digging deeper into the Southern skies: a compact Milky-Way companion discovered in first-year Dark Energy Survey data
• Alignments between galaxies, satellite systems and haloes
• A new spin on disks of satellite galaxies
• The accretion of dark matter subhaloes within the cosmic web: primordial anisotropic distribution and its universality
• Assembly of filamentary void galaxy configurations
• The Role of Baryons in Creating Statistically Significant Planes of Satellites around Milky Way-Mass Galaxies
• Satellite Alignment: I. Distribution of Substructures and Their Dependence On Assembly History From N-Body Simulations
• Evidence for Early Filamentary Accretion from the Andromeda Galaxy's Thin Plane of Satellites
• On the stark difference in satellite distributions around the Milky Way and Andromeda
• Co-orbiting planes of sub-halos are similarly unlikely around paired and isolated hosts
• The tangential velocity excess of the Milky Way satellites
• A Formation Scenario for the Disk of Satellites: Accretion of Satellites during Mergers
• The orbital PDF: the dynamical state of Milky Way sized haloes and the intrinsic uncertainty in the determination of their masses
• Subhalo accretion through filaments
• ZOMG III: The effect of Halo Assembly on the Satellite Population
• Subhaloes gone Notts: Subhaloes as tracers of the dark matter halo shape

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• From galactic bars to the Hubble tension: weighing up the astrophysical evidence for Milgromian gravity
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• The Milky Way's Disk of Classical Satellite Galaxies in Light of Gaia DR2
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• A Lonely Giant: The Sparse Satellite Population of M94 Challenges Galaxy Formation
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• Dark and luminous satellites of LMC-mass galaxies in the FIRE simulations
• Tracing satellite planes in the Sculptor group: I. Discovery of three faint dwarf galaxies around NGC 253
• Origin of the Local Group satellite planes
• Evolution of galactic planes of satellites in the EAGLE simulation
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• Satellites of Satellites: The Case for Carina and Fornax
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• Morphological and Rotation Structures of Circumgalactic Mg II Gas in the EAGLE Simulation and the Dependence on Galaxy Properties
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• The orientation of planes of dwarf galaxies in the quasi-linear Universe
• Resolving 3D Disk Orientation using High-Resolution Images: New Constraints on Circumgalactic Gas Inflows
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• Do halos that form early, have high concentration, are part of a pair, or contain a central galaxy potential host more pronounced planes of satellite galaxies?
• Models of Distorted and Evolving Dark Matter Halos
• Alignment between satellite and central galaxies in the SDSS DR7: dependence on large-scale environment
• The impact of filamentary accretion of subhaloes on the shape and orientation of haloes
• Orbital distribution of infalling satellite halos across cosmic time
• The effect of Large Magellanic Cloud on the satellite galaxy population in Milky Way analogous Galaxies
• A portrait of the Vast Polar Structure as a young phenomenon: hints from its member satellites
• The lopsided distribution of satellites of isolated central galaxies
• EDGE: The shape of dark matter haloes in the faintest galaxies
• The satellite galaxy plane of NGC 4490 in light of ΛCDM - Sparsity of similarly extreme analogs and a possible role of satellite pairs
• The imprint of galaxy mergers on satellite planes in a cosmological context
• On the absence of backsplash analogues to NGC 3109 in the $\Lambda$CDM framework
• Satellite group infall into the Milky Way: exploring the Crater-Leo case with new HST proper motions
• Anisotropic satellite accretion onto the Local Group with HESTIA
• Auriga Streams I: disrupting satellites surrounding Milky Way-mass haloes at multiple resolutions
• The Magellanic Clouds are very rare in the IllustrisTNG simulations
• Determining Satellite Infall Times Using Machine Learning
• The spatial distribution of satellites in galaxy clusters
• Satellites and central galaxies in SDSS: the influence of interactions on their properties
• Subhalos are Anisotropically Distributed and Aligned with the Smooth Matter Distribution of Their Host Halos
• DELVE Milky Way Satellite Galaxy Census I: Satellite Population and Survey Selection Function in DES, DELVE, and Pan-STARRS
• Subhalo abundance and satellite spatial distribution in Milky Way-Andromeda-like paired haloes