Extending the SAGA Survey (xSAGA) I: Satellite Radial Profiles as a Function of Host Galaxy Properties

Abstract

We present "Extending the Satellites Around Galactic Analogs Survey" (xSAGA), a method for identifying low-$z$ galaxies on the basis of optical imaging, and results on the spatial distributions of xSAGA satellites around host galaxies. Using spectroscopic redshift catalogs from the SAGA Survey as a training data set, we have optimized a convolutional neural network (CNN) to identify $z<0.03$ galaxies from more distant objects using image cutouts from the DESI Legacy Imaging Surveys. From the sample of $>100,000$ CNN-selected low-$z$ galaxies, we identify $>20,000$ probable satellites located between 36-300 projected kpc from NASA-Sloan Atlas central galaxies in the stellar mass range $9.5<\log (M_{\star }/M_{\odot })<11$. We characterize the incompleteness and contamination for CNN-selected samples, and apply corrections in order to estimate the true number of satellites as a function of projected radial distance from their hosts. Satellite richness depends strongly on host stellar mass, such that more massive host galaxies have more satellites, and on host morphology, such that elliptical hosts have more satellites than disky hosts with comparable stellar masses. We also find a strong inverse correlation between satellite richness and the magnitude gap between a host and its brightest satellite. The normalized satellite radial distribution between 36-300 kpc does not depend strongly on host stellar mass, morphology, or magnitude gap. The satellite abundances and radial distributions we measure are in reasonable agreement with predictions from hydrodynamic simulations. Our results deliver unprecedented statistical power for studying satellite galaxy populations, and highlight the promise of using machine learning for extending galaxy samples of wide-area surveys.

arXiv comment27 pages, 18 figures, 1 table. Accepted to ApJ. Code available at https://github.com/jwuphysics/xsaga

References in corpus (112)

• Astropy: A Community Python Package for Astronomy
• The NumPy array: a structure for efficient numerical computation
• The Sloan Digital Sky Survey: Technical Summary
• A Universal Density Profile from Hierarchical Clustering
• Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
• The EAGLE project: Simulating the evolution and assembly of galaxies and their environments
• Dark Matter Substructure in Galactic Halos
• Stellar Masses and Star Formation Histories for 10^5 Galaxies from the Sloan Digital Sky Survey
• Profiles of dark haloes: evolution, scatter, and environment
• Statistical Properties of X-ray Clusters: Analytic and Numerical Comparisons
• Simulating Galaxy Formation with the IllustrisTNG Model
• The observed properties of dwarf galaxies in and around the Local Group
• Overview of the DESI Legacy Imaging Surveys
• The Galaxy in Context: Structural, Kinematic and Integrated Properties
• Small-Scale Challenges to the $\Lambda$CDM Paradigm
• Physical Models of Galaxy Formation in a Cosmological Framework
• UniverseMachine: The Correlation between Galaxy Growth and Dark Matter Halo Assembly from z=0-10
• GIZMO: A New Class of Accurate, Mesh-Free Hydrodynamic Simulation Methods
• FIRE-2 Simulations: Physics versus Numerics in Galaxy Formation
• Galaxy and Mass Assembly (GAMA): survey diagnostics and core data release
• The Hyper Suprime-Cam SSP Survey: Overview and Survey Design
• The Dark Energy Survey: more than dark energy - an overview
• fastai: A Layered API for Deep Learning
• The Connection between Galaxies and their Dark Matter Halos
• Rotation-invariant convolutional neural networks for galaxy morphology prediction
• Reconciling dwarf galaxies with LCDM cosmology: Simulating a realistic population of satellites around a Milky Way-mass galaxy
• The tumultuous lives of galactic dwarfs and the missing satellites problem
• Formation and evolution of galaxy dark matter halos and their substructure
• Improved background subtraction for the Sloan Digital Sky Survey images
• COLOSSUS: A python toolkit for cosmology, large-scale structure, and dark matter halos
• Accurate universal models for the mass accretion histories and concentrations of dark matter halos
• Hundreds of Milky Way Satellites? Luminosity Bias in the Satellite Luminosity Function
• Not so lumpy after all: modeling the depletion of dark matter subhalos by Milky Way-like galaxies
• Baryons Matter: Why Luminous Satellite Galaxies Have Reduced Central Masses
• The Romulus Cosmological Simulations: A Physical Approach to the Formation, Dynamics and Accretion Models of SMBHs
• Why Baryons Matter: The Kinematics of Dwarf Spheroidal Satellites
• The splashback radius as a physical halo boundary and the growth of halo mass
• The Anisotropic Distribution of Galactic Satellites
• The Radial Distribution of Galaxies in LCDM clusters
• Semi-Analytic Galaxy Evolution (SAGE): Model Calibration and Basic Results
• Cold gas stripping in satellite galaxies: from pairs to clusters
• The SAGA Survey: I. Satellite Galaxy Populations Around Eight Milky Way Analogs
• There is No Missing Satellites Problem
• The Local Group on FIRE: Dwarf galaxy populations across a suite of hydrodynamic simulations
• Milky Way Satellite Census. II. Galaxy--Halo Connection Constraints Including the Impact of the Large Magellanic Cloud
• Photometric redshifts from SDSS images using a Convolutional Neural Network
• The SAGA Survey. II. Building a Statistical Sample of Satellite Systems around Milky Way-like Galaxies
• PAndAS' progeny: extending the M31 dwarf galaxy cabal
• Characterization of subhalo structural properties and implications for dark matter annihilation signals
• Milky Way Satellite Census. I. The Observational Selection Function for Milky Way Satellites in DES Y3 and Pan-STARRS DR1
• Illuminating Low-Surface-Brightness Galaxies with the Hyper Suprime-Cam Survey
• The PAndAS view of the Andromeda satellite system - II. Detailed properties of 23 M31 dwarf spheroidal galaxies
• NIHAO XV: The environmental impact of the host galaxy on galactic satellite and field dwarf galaxies
• Satellite abundances around bright isolated galaxies
• Organized Chaos: Scatter in the relation between stellar mass and halo mass in small galaxies
• Small-Scale Structure in the SDSS and LCDM: Isolated L* Galaxies with Bright Satellites
• How Common are the Magellanic Clouds?
• Phat ELVIS: The inevitable effect of the Milky Way's disk on its dark matter subhaloes
• A profile in FIRE: resolving the radial distributions of satellite galaxies in the Local Group with simulations
• Rapid Environmental Quenching of Satellite Dwarf Galaxies in the Local Group
• The satellite distribution of M31
• The DECam Local Volume Exploration Survey: Overview and First Data Release
• Statistics of Satellite Galaxies Around Milky Way-Like Hosts
• Shadows in the Dark: Low-Surface-Brightness Galaxies Discovered in the Dark Energy Survey
• The Dependence of Subhalo Abundance on Halo Concentration
• The Eating Habits of Milky Way Mass Halos: Destroyed Dwarf Satellites and the Metallicity Distribution of Accreted Stars
• Hints on the Nature of Dark Matter from the Properties of Milky Way Satellites
• ELVES I: Structures of Dwarf Satellites of MW-like Galaxies; Morphology, Scaling Relations, and Intrinsic Shapes
• The Abundance and Radial Distribution of Satellite Galaxies
• Satellites and Haloes of Dwarf Galaxies
• Deeply Uncertain: Comparing Methods of Uncertainty Quantification in Deep Learning Algorithms
• The dwarf galaxy satellite system of Centaurus A
• The Three Causes of Low-Mass Assembly Bias
• Modeling the Connection Between Subhalos and Satellites in Milky Way-like Systems
• The tidal evolution of dark matter substructure -- II. The impact of artificial disruption on subhalo mass functions and radial profiles
• Resolved Dwarf Galaxy Searches within ~5 Mpc with the Vera Rubin Observatory and Subaru Hyper Suprime-Cam
• Subhalo destruction in the Apostle and Auriga simulations
• The distinct stellar-to-halo mass relations of satellite and central galaxies: insights from the IllustrisTNG simulations
• Photometric Redshift Estimation with a Convolutional Neural Network: NetZ
• The Milky Way's Halo and Subhalos in Self-Interacting Dark Matter
• Reignition of Star Formation in Dwarf Galaxies
• Modeling the Impact of Baryons on Subhalo Populations with Machine Learning
• The Satellite Luminosity Functions of Galaxies in SDSS
• A Deep Search for Extended Radio Continuum Emission From Dwarf Spheroidal Galaxies: Implications for Particle Dark Matter
• Luminosity Functions and Host-to-Host Scatter of Dwarf Satellite Systems in the Local Volume
• How low does it go? Too few Galactic satellites with standard reionization quenching
• Tracing satellite planes in the Sculptor group: I. Discovery of three faint dwarf galaxies around NGC 253
• Luminous Satellites II: Spatial Distribution, Luminosity Function and Cosmic Evolution
• Radial Distributions of Dwarf Satellite Systems in the Local Volume
• Using convolutional neural networks to predict galaxy metallicity from three-color images
• Measuring distances to low-luminosity galaxies using surface brightness fluctuations
• Flybys, orbits, splashback: subhalos and the importance of the halo boundary
• Mind the Gap: Tightening the Mass-Richness Relation with Magnitude Gaps
• The Morphology-Density-Relation: Impact on the Satellite Fraction
• The Cosmic Abundance of Classical Milky Way Satellites
• On the stark difference in satellite distributions around the Milky Way and Andromeda
• The AGORA High-resolution Galaxy Simulations Comparison Project. III: Cosmological zoom-in simulation of a Milky Way-mass halo
• A comparative study of satellite galaxies in Milky Way-like galaxies from HSC, DECaLS and SDSS
• And In The Darkness Unbind Them: High-Resolution Simulations of Dark Matter Subhalo Disruption in a Milky Way-like Tidal Field
• Where are All the Gas-Bearing Local Dwarf Galaxies? Quantifying Possible Impacts of Reionization
• SatGen -- II. Assessing the impact of a disc potential on subhalo populations
• Characterising the target selection pipeline for the Dark Energy Spectroscopic Instrument Bright Galaxy Survey
• Subhaloes in Scale-Free Cosmologies
• Aging Halos: Implications of the Magnitude Gap on Conditional Statistics of Stellar and Gas Properties of Massive Halos
• Magnitude Gap Statistics and the Conditional Luminosity Function
• A Search for Satellite Galaxies of Nearby Star-Forming Galaxies with Resolved Stars in LBT-SONG
• Exploring extensions to the standard cosmological model and the impact of baryons on small scales
• The abundance of satellites depends strongly on the morphology of the host galaxy
• Connecting optical morphology, environment, and HI mass fraction for low-redshift galaxies using deep learning
• On the limits of measuring the bulge and disk properties of local and high-redshift massive galaxies
• MIND THE GAP: Is The Too Big To Fail Problem Resolved?
• The Formation of M101-alike Galaxies in the Cold Dark Matter Model