Milky Way-est: Cosmological Zoom-in Simulations with Large Magellanic Cloud and Gaia-Sausage-Enceladus Analogs

Abstract

We present Milky Way-est, a suite of 20 cosmological cold-dark-matter-only zoom-in simulations of Milky Way (MW)-like host halos. Milky Way-est hosts are selected such that they (i) are consistent with the MW's measured halo mass and concentration, (ii) accrete a Large Magellanic Cloud (LMC)-like ($\approx 10^{11}{M}_{\odot }$) subhalo within the last $2\mathrm{Gyr}$ on a realistic orbit, placing them near $50\mathrm{kpc}$ from the host center at $z\approx 0$, and (iii) undergo a $>$1:5 sub-to-host halo mass ratio merger with a Gaia-Sausage-Enceladus (GSE)-like system at early times ($0.67<z<3$). Hosts satisfying these LMC and GSE constraints constitute $<1\%$ of all halos in the MW's mass range, and their total masses grow rapidly at late times due to LMC analog accretion. Compared to hosts of a similar final halo mass that are not selected to include LMC and GSE analogs, Milky Way-est hosts contain $22\%$ more subhalos with present-day virial masses above $10^8{M}_{\odot }$ throughout the virial radius, on average. This enhancement reaches $\approx 80\%$ in the inner $100\mathrm{kpc}$ and is largely, if not entirely, due to LMC-associated subhalos. These systems also induce spatial anisotropy in Milky Way-est subhalo populations, with $\approx 60\%$ of the total subhalo population within $100\mathrm{kpc}$ found in the current direction of the LMC. Meanwhile, we find that GSE-associated subhalos do not significantly contribute to present-day Milky Way-est subhalo populations. These results provide context for our Galaxy's dark matter structure and subhalo population and will help interpret a range of measurements that are currently only possible in the MW.

arXiv comment19 pages, 10 figures, 2 tables. Updated to published version

References in corpus (114)

• A Universal Density Profile from Hierarchical Clustering
• The cosmological simulation code GADGET-2
• Nine-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Parameter Results
• Statistical Properties of X-ray Clusters: Analytic and Numerical Comparisons
• The Aquarius Project: the subhalos of galactic halos
• The Apache Point Observatory Galactic Evolution Experiment (APOGEE)
• The Rockstar Phase-Space Temporal Halo Finder and the Velocity Offsets of Cluster Cores
• UniverseMachine: The Correlation between Galaxy Growth and Dark Matter Halo Assembly from z=0-10
• The merger that led to the formation of the Milky Way's inner stellar halo and thick disk
• Co-formation of the Galactic disc and the stellar halo
• Clumps and streams in the local dark matter distribution
• Multi-scale initial conditions for cosmological simulations
• A distance to the Large Magellanic Cloud that is precise to one per cent
• Reconciling dwarf galaxies with LCDM cosmology: Simulating a realistic population of satellites around a Milky Way-mass galaxy
• Gravitationally Consistent Halo Catalogs and Merger Trees for Precision Cosmology
• The tumultuous lives of galactic dwarfs and the missing satellites problem
• The APOSTLE simulations: solutions to the Local Group's cosmic puzzles
• New Understanding of Large Magellanic Cloud Structure, Dynamics and Orbit from Carbon Star Kinematics
• Are the Magellanic Clouds on their First Passage about the Milky Way?
• Third-Epoch Magellanic Cloud Proper Motions I: HST/WFC3 data and Orbit Implications
• Streams, substructures and the early history of the Milky Way
• Evidence from the H3 Survey that the Stellar Halo is Entirely Comprised of Substructure
• The total mass of the Large Magellanic Cloud from its perturbation on the Orphan stream
• Not so lumpy after all: modeling the depletion of dark matter subhalos by Milky Way-like galaxies
• The Milky Way total mass profile as inferred from Gaia DR2
• ELVIS: Exploring the Local Volume in Simulations
• Milky Way Satellite Census. III. Constraints on Dark Matter Properties from Observations of Milky Way Satellite Galaxies
• Third-Epoch Magellanic Cloud Proper Motions II: The Large Magellanic Cloud Rotation Field in Three Dimensions
• Kraken reveals itself -- the merger history of the Milky Way reconstructed with the E-MOSAICS simulations
• The SAGA Survey: I. Satellite Galaxy Populations Around Eight Milky Way Analogs
• There's no place like home? Statistics of Milky Way-mass dark matter halos
• From dawn till disk: Milky Way's turbulent youth revealed by the APOGEE+Gaia data
• Milky Way Satellite Census. II. Galaxy--Halo Connection Constraints Including the Impact of the Large Magellanic Cloud
• Hunting for the Dark Matter Wake Induced by the Large Magellanic Cloud
• The Spur and the Gap in GD-1: Dynamical evidence for a dark substructure in the Milky Way halo
• SubHaloes going Notts: The SubHalo-Finder Comparison Project
• The SAGA Survey. II. Building a Statistical Sample of Satellite Systems around Milky Way-like Galaxies
• Small Dwarf Galaxies Within Larger Dwarfs: Why Some Are Luminous While Most Go Dark
• The Orbital Histories of Magellanic Satellites Using Gaia DR2 Proper Motions
• Milky Way Satellite Census. I. The Observational Selection Function for Milky Way Satellites in DES Y3 and Pan-STARRS DR1
• Reconstructing the Last Major Merger of the Milky Way with the H3 Survey
• The mass of the Milky Way from satellite dynamics
• A Magellanic Origin of the DES Dwarfs
• Overview of the DESI Milky Way Survey
• Ultra-faint dwarfs in a Milky Way context: Introducing the Mint Condition DC Justice League Simulations
• The Missing Satellites of the Magellanic Clouds? Gaia Proper Motions of the Recently Discovered Ultra-Faint Galaxies
• The origin of galactic metal-rich stellar halo components with highly eccentric orbits
• Star formation histories of dwarf galaxies in the FIRE simulations: dependence on mass and Local Group environment
• The Concentration Dependence of the Galaxy-Halo Connection: Modeling Assembly Bias with Abundance Matching
• The mass of our Milky Way
• How Common are the Magellanic Clouds?
• Phat ELVIS: The inevitable effect of the Milky Way's disk on its dark matter subhaloes
• The Hestia project: simulations of the Local Group
• Sausage & Mash: The dual origin of the Galactic thick disc and halo from the gas-rich Gaia-Enceladus-Sausage merger
• Quantifying the impact of the Large Magellanic Cloud on the structure of the Milky Way's dark matter halo using Basis Function Expansions
• Sussing Merger Trees: The Merger Trees Comparison Project
• Measuring the Mass of the Large Magellanic Cloud with Stellar Streams Observed by $S^5$
• The Caterpillar Project: A Large Suite of Milky Way Sized Halos
• The detailed structure and the onset of galaxy formation in low-mass gaseous dark matter haloes
• All-Sky Dynamical Response of the Galactic Halo to the Large Magellanic Cloud
• Statistics of Satellite Galaxies Around Milky Way-Like Hosts
• Limit on the LMC mass from a census of its satellites
• A Quantification of the Butterfly Effect in Cosmological Simulations and Implications for Galaxy Scaling Relations
• Satellites of LMC-Mass Dwarfs: Close Friendships Ruined by Milky Way Mass Halos
• The last breath of the Sagittarius dSph
• Detection of the Milky Way reflex motion due to the Large Magellanic Cloud infall
• The Dependence of Subhalo Abundance on Halo Concentration
• The ARTEMIS simulations: stellar haloes of Milky Way-mass galaxies
• Identifying true satellites of the Magellanic Clouds
• The Formation Times and Building Blocks of Milky Way-mass Galaxies in the FIRE Simulations
• The predicted luminous satellite populations around SMC and LMC-mass galaxies - A missing satellite problem around the LMC?
• Evidence of a population of dark subhalos from Gaia and Pan-STARRS observations of the GD-1 stream
• Clues to the "Magellanic Galaxy" from Cosmological Simulations
• Planes of satellites around Milky Way/M31-mass galaxies in the FIRE simulations and comparisons with the Local Group
• The DECam Local Volume Exploration Survey Data Release 2
• Modeling the Connection Between Subhalos and Satellites in Milky Way-like Systems
• EDGE: The origin of scatter in ultra-faint dwarf stellar masses and surface brightnesses
• The effect of the LMC on the Milky Way system
• Constrained Local UniversE Simulations: A Local Group Factory
• The effect of the deforming dark matter haloes of the Milky Way and the Large Magellanic Cloud on the Orphan-Chenab stream
• Modeling the Impact of Baryons on Subhalo Populations with Machine Learning
• The Stellar Halo of the Galaxy is Tilted & Doubly Broken
• A Gaia-Enceladus Analog in the EAGLE Simulation: Insights into the Early Evolution of the Milky Way
• Merger-induced galaxy transformations in the ARTEMIS simulations
• Under the Firelight: Stellar Tracers of the Local Dark Matter Velocity Distribution in the Milky Way
• On the Segregation of Dark Matter Substructure
• Strong Dark Matter Self-interactions Diversify Halo Populations within and surrounding the Milky Way
• Symphony: Cosmological Zoom-in Simulation Suites over Four Decades of Host Halo Mass
• How low does it go? Too few Galactic satellites with standard reionization quenching
• Dark and luminous satellites of LMC-mass galaxies in the FIRE simulations
• The little things matter: relating the abundance of ultrafaint satellites to the hosts' assembly history
• GRUMPY: a simple framework for realistic forward-modelling of dwarf galaxies
• The highest-speed local dark matter particles come from the Large Magellanic Cloud
• Magellanic satellites in $\Lambda$CDM cosmological hydrodynamical simulations of the Local Group
• On the stark difference in satellite distributions around the Milky Way and Andromeda
• The Clustering of Orbital Poles Induced by the LMC: Hints for the Origin of Planes of Satellites
• The infall of dwarf satellite galaxies are influenced by their host's massive accretions
• How Unusual is the Milky Way's Assembly History?
• The Effects of Dark Matter and Baryonic Physics on the Milky Way Subhalo Population in the Presence of the Large Magellanic Cloud
• Forecasts for Galaxy Formation and Dark Matter Constraints from Dwarf Galaxy Surveys
• Formation of Galactic Disks I: Why Did the Milky Way's Disk Form Unusually Early?
• Predictably Missing Satellites: Subhalo Abundance in Milky Way-like Halos
• VINTERGATAN-GM: The cosmological imprints of early mergers on Milky-Way-mass galaxies
• The impact of the Large Magellanic Cloud on dark matter direct detection signals
• UniverseMachine: Predicting Galaxy Star Formation over Seven Decades of Halo Mass with Zoom-in Simulations
• The connection between the host halo and the satellite galaxies of the Milky Way
• Illuminating Dark Matter Halo Density Profiles Without Subhaloes
• Taking the Milky Way for a spin: disc formation in the ARTEMIS simulations
• The dark side of FIRE: predicting the population of dark matter subhaloes around Milky Way-mass galaxies
• Informing dark matter direct detection limits with the ARTEMIS simulations
• The Milky Way, Coming into Focus: Precision Astrometry Probes its Evolution, and its Dark Matter
• Growing the First Galaxies' Merger Trees
• A high fidelity Milky Way simulation with Kraken, Gaia-Enceladus, and Sequoia analogues: clues to their accretion histories
• Massively Parallel Computation of Accurate Densities for N-body Dark Matter Simulations using the Phase-Space-Element Method

Cited by in corpus (18)

• The SAGA Survey. III. A Census of 101 Satellite Systems around Milky Way-mass Galaxies
• The Escape Velocity Profile of the Milky Way from Gaia DR3
• Vertical structure and kinematics of the LMC disc from SDSS/Gaia
• COZMIC. I. Cosmological Zoom-in Simulations with Initial Conditions Beyond Cold Dark Matter
• The Impact of Molecular Hydrogen Cooling on the Galaxy Formation Threshold
• Mixed Warm Dark Matter Constraints using Milky Way Satellite Galaxy Counts
• Shaping the Milky Way: The interplay of mergers and cosmic filaments
• SIDM Concerto: Compilation and Data Release of Self-interacting Dark Matter Zoom-in Simulations
• The Effects of Linear Matter Power Spectrum Enhancement on Dark Matter Substructure
• COZMIC. II. Cosmological Zoom-in Simulations with Fractional non-CDM Initial Conditions
• Cosmological Simulations of Stellar Halos with Gaia Sausage-Enceladus Analogues: Two Sausages, One Bun?
• EDEN: Exploring Disks Embedded in N-body simulations of Milky-Way-mass halos from Symphony
• COZMIC. III. Cosmological Zoom-in Simulations of Self-interacting Dark Matter with Suppressed Initial Conditions
• The effect of environment on the mass assembly history of the Milky Way and M31
• DELVE Milky Way Satellite Galaxy Census I: Satellite Population and Survey Selection Function in DES, DELVE, and Pan-STARRS
• The DORCHA suite: nature, nurture, and the phase space distribution of the Milky Way's high redshift progenitors today
• How to Build an Empirical Speed Distribution for Dark Matter in the Solar Neighborhood
• Bulgeless Evolution And the Rise of Discs (BEARD) III. A numerical simulation view of satellites around Milky-Way analogues