The Caterpillar Project: A Large Suite of Milky Way Sized Halos

Abstract

We present the largest number of Milky Way sized dark matter halos simulated at very high mass ($\sim$$10^4$ M${}_{\odot }$/particle) and temporal resolution ($\sim$5 Myrs/snapshot) done to date, quadrupling what is currently available in the literature. This initial suite consists of the first 24 halos of the $Caterpillar$ $Project$ (www.caterpillarproject.org) whose project goal of 60 - 70 halos will be made public when complete. We resolve $\sim$20,000 gravitationally bound subhalos within the virial radius of each host halo. Over the ranges set by our spatial resolution our convergence is excellent and improvements were made upon current state-of-the-art halo finders to better identify substructure at such high resolutions (e.g., on average we recover $\sim$4 subhalos in each host halo above 10${}^8$ M${}_{\odot }$ which would have otherwise not been found using conventional methods). For our relaxed halos, the inner profiles are reasonably fit by Einasto profiles ($\alpha$ = 0.169 $\pm$ 0.023) though this depends on the relaxed nature and assembly history of a given halo. Averaging over all halos, the substructure mass fraction is $f_{m,subs}=0.121\pm 0.041$, and mass function slope is d$N$/d$M\propto M^{-1.88\pm 0.10}$ though we find scatter in the normalizations for fixed halo mass due to more concentrated hosts having less subhalos at fixed subhalo mass. There are no biases stemming from Lagrangian volume selection as all Lagrangian volume types are included in our sample. Our detailed contamination study of 264 low resolution halos has resulted in obtaining very large and unprecedented, high-resolution regions around our host halos for our target resolution (sphere of radius $\sim$$1.4\pm 0.4$ Mpc) allowing for accurate studies of low mass dwarf galaxies at large galactocentric radii and the very first stellar systems at high redshift ($z\ge$ 10).

19 pages; 14 figures; 6 tables; Received September 3, 2015; Accepted November 15, 2015; Published February 2, 2016

References in corpus (24)

• The EAGLE project: Simulating the evolution and assembly of galaxies and their environments
• Introducing the Illustris Project: Simulating the coevolution of dark and visible matter in the Universe
• Too big to fail? The puzzling darkness of massive Milky Way subhaloes
• The Radial Velocity Experiment (RAVE): first data release
• The Milky Way's Circular Velocity Curve to 60 kpc and an Estimate of the Dark Matter Halo Mass from Kinematics of ~2400 SDSS Blue Horizontal Branch Stars
• The RAVE Survey: Constraining the Local Galactic Escape Speed
• Near-Field Cosmology with Metal-Poor Stars
• Tracing Galaxy Formation with Stellar Halos II: Relating Substructure in Phase- and Abundance-Space to Accretion Histories
• Core Formation in Dwarf Halos with Self Interacting Dark Matter: No Fine-Tuning Necessary
• The M31 Velocity Vector. II. Radial Orbit Towards the Milky Way and Implied Local Group Mass
• The stellar halo of the Galaxy
• Too Big to Fail in the Local Group
• Segue 1: An Unevolved Fossil Galaxy from the Early Universe
• SubHaloes going Notts: The SubHalo-Finder Comparison Project
• Building Late-Type Spiral Galaxies by In-Situ and Ex-Situ Star Formation
• The Space Motion of Leo I: Hubble Space Telescope Proper Motion and Implied Orbit
• Estimating the dark matter halo mass of our Milky Way using dynamical tracers
• The emptiness of voids: yet another over-abundance problem for the LCDM model
• A unified solution to the small scale problems of the $\Lambda$CDM model
• Evidence for Early Filamentary Accretion from the Andromeda Galaxy's Thin Plane of Satellites
• Environmental Influences on the Morphology and Dynamics of Group Size Haloes
• Comparing Planck and WMAP: Maps, Spectra, and Parameters
• The Effects of Varying Cosmological Parameters on Halo Substructure
• On the Environmental Dependence of Galaxy Properties Established by the Initial Cosmological Conditions

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• Observational constraints on the survival of pristine stars
• Search for $\gamma$-ray emission from dark matter particle interactions from Andromeda and Triangulum Galaxies with the Fermi Large Area Telescope
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• The dark side of FIRE: predicting the population of dark matter subhaloes around Milky Way-mass galaxies
• Tracing stars in Milky Way satellites with A-SLOTH
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• Boltzmann hierarchies for self-interacting warm dark matter scenarios
• An Accurate Comprehensive Approach to Substructure: I. Accreted Subhaloes
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• Dark Matter Annihilation Feedback in Cosmological Simulations II: The Influence on Gas and Halo Structure
• Dark sector domain walls could explain the observed planes of satellites
• DELVE-DEEP Survey: The Faint Satellite System of NGC 55
• Comparing simulated Milky Way satellite galaxies with observations using unsupervised clustering
• Densities and mass assembly histories of the Milky Way satellites are not a challenge to $\Lambda$CDM
• An Accurate Comprehensive Approach to Substructure: IV. Dynamical Friction
• Forward-modelling the Luminosity, Distance, and Size distributions of the Milky Way Satellites
• Excess of substructure due to primordial black holes