The Hierarchical Structure of Galactic Haloes: Classification and characterisation with Halo-OPTICS

Abstract

We build upon Ordering Points To Identify Clustering Structure (OPTICS), a hierarchical clustering algorithm well-known to be a robust data-miner, in order to produce Halo-OPTICS, an algorithm designed for the automatic detection and extraction of all meaningful clusters between any two arbitrary sizes. We then apply Halo-OPTICS to the 3D spatial positions of halo particles within four separate synthetic Milky Way type galaxies, classifying the stellar and dark matter structural hierarchies. Through visualisation of the Halo-OPTICS output, we compare its structure identification to the state-of-the-art galaxy/(sub)halo finder VELOCIraptor, finding excellent agreement even though Halo-OPTICS does not consider kinematic information in this current implementation. We conclude that Halo-OPTICS is a robust hierarchical halo finder, although its determination of lower spatial-density features such as the tails of streams could be improved with the inclusion of extra localised information such as particle kinematics and stellar metallicity into its distance metric.

arXiv comment18 pages, 12 figures, 2 tables. Accepted by MNRAS

References in corpus (65)

• Scikit-learn: Machine Learning in Python
• Gaia Data Release 2. Summary of the contents and survey properties
• The Structure of Cold Dark Matter Halos
• 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
• Sloan Digital Sky Survey IV: Mapping the Milky Way, Nearby Galaxies, and the Distant Universe
• The Rockstar Phase-Space Temporal Halo Finder and the Velocity Offsets of Cluster Cores
• A Multi-Code Analysis Toolkit for Astrophysical Simulation Data
• Halo Formation in Warm Dark Matter Models
• The Inner Structure of LambdaCDM Halos I: A Numerical Convergence Study
• Ahf: Amiga's Halo Finder
• Reionization and the abundance of galactic satellites
• Accurate masses for dispersion-supported galaxies
• The subhalo populations of LCDM dark haloes
• Reconciling dwarf galaxies with LCDM cosmology: Simulating a realistic population of satellites around a Milky Way-mass galaxy
• The remnants of galaxy formation from a panoramic survey of the region around M31
• The APOSTLE simulations: solutions to the Local Group's cosmic puzzles
• Formation and evolution of galaxy dark matter halos and their substructure
• Dark Matter Halos within Clusters
• Can Photoionization Squelching Resolve the Sub-structure Crisis?
• Halo Substructure And The Power Spectrum
• Haloes gone MAD: The Halo-Finder Comparison Project
• Substructure and halo density profiles in a Warm Dark Matter Cosmology
• Hundreds of Milky Way Satellites? Luminosity Bias in the Satellite Luminosity Function
• The Effects of Photoionization on Galaxy Formation - II: Satellites in the Local Group
• The Luminosity Function of the Milky Way Satellites
• ELVIS: Exploring the Local Volume in Simulations
• Why Baryons Matter: The Kinematics of Dwarf Spheroidal Satellites
• The Pristine survey I: Mining the Galaxy for the most metal-poor stars
• Halo and Subhalo Demographics with Planck Cosmological Parameters: Bolshoi-Planck and MultiDark-Planck Simulations
• The dearth of halo dwarf galaxies: is there power on short scales?
• There is No Missing Satellites Problem
• Formation Histories of Dwarf Galaxies in the Local Group
• Globular clusters, satellite galaxies and stellar haloes from early dark matter peaks
• The hidden giant: discovery of an enormous Galactic dwarf satellite in Gaia DR2
• A kinematic classification of the cosmic web
• The large-scale structure of the halo of the Andromeda galaxy II. Hierarchical structure in the Pan-Andromeda Archaeological Survey
• The Invisibles: A Detection Algorithm to Trace the Faintest Milky Way Satellites
• The chosen few: the low mass halos that host faint galaxies
• The overdensity and masses of the friends-of-friends halos and universality of the halo mass function
• The total satellite population of the Milky Way
• Baryonic impact on the dark matter distribution in Milky Way-size galaxies and their satellites
• Snake in the Clouds: A new nearby dwarf galaxy in the Magellanic bridge
• The Fate of Substructures in Cold Dark Matter Haloes
• M31 Satellite Masses Compared to LCDM Subhaloes
• Dark Matter Subhaloes in Numerical Simulations
• Hunting for Galaxies and Halos in simulations with VELOCIraptor
• A Complete Spectroscopic Survey of the Milky Way satellite Segue 1: Dark matter content, stellar membership and binary properties from a Bayesian analysis
• The Cosmogrid Simulation: Statistical Properties of Small Dark Matter Halos
• Dark Matter Halos with Cores from Hierarchical Structure Formation
• NIHAO V: Too big doesn't fail -- reconciling the conflict between LCDM predictions and the circular velocities of nearby field galaxies
• Stealth Galaxies in the Halo of the Milky Way
• Peaks above the Maxwellian Sea: A New Approach to Finding Substructure in N-Body Haloes
• SURFS: Riding the waves with Synthetic UniveRses For Surveys
• Boötes IV: A New Milky Way Satellite Discovered in the Subaru Hyper Suprime-Cam Survey and Implications for the Missing Satellite Problem
• Stacking the Invisibles: A Guided Search for Low-Luminosity Milky Way Satellites
• A census of $\rho$ Oph candidate members from Gaia DR2
• Deciphering the large-scale environment of radio galaxies in the local Universe: where do they born, grow and die?
• Predictably Missing Satellites: Subhalo Abundance in Milky Way-like Halos
• A faint halo star cluster discovered in the Blanco Imaging of the Southern Sky Survey
• Assembly history of subhalo populations in galactic and cluster sized dark haloes
• Extended Stellar Components of Galaxies & the Nature of Dark Matter

Cited by in corpus (3)

• Data mining techniques on astronomical spectra data. I : Clustering Analysis
• Uncovering fossils of the distant Milky Way with UNIONS: NGC 5466 and its stellar stream
• The Hierarchical Structure of Galactic Haloes: Generalised N-Dimensional Clustering with CluSTAR-ND