Conditional Colour-Magnitude Distribution of Central Galaxies in Galaxy Formation Models

Abstract

We investigate the conditional colour-magnitude distribution (CCMD), namely the colour-magnitude distribution at fixed halo mass, of the central galaxies in semi-analytic galaxy formation model (SAM) and hydrodynamic simulations. We analyse the CCMD of central galaxies in each halo mass bin with the Gaussian mixture model and find that it can be decomposed into red and blue components nearly orthogonal to each other, a red component narrow in colour and extended in magnitude and a blue component narrow in magnitude and extended in colour. We focus on the SAM galaxies to explore the origin of the CCMD components by studying the relation between central galaxy colour and halo or galaxy properties. Central galaxy colour is correlated with halo assembly properties for low mass haloes and independent of them for high mass haloes. Galaxy properties such as central supermassive black hole mass, cold gas mass, and gas specific angular momentum can all impact central galaxy colour. These results are corroborated by an alternative machine learning analysis in which we attempt to predict central galaxy colour with halo and galaxy properties. We find that the prediction for colours of central galaxies can be significantly improved using both halo and galaxy properties as input compared to using halo properties alone. With the halo and galaxy properties considered here, we find that subtle discrepancies remain between predicted and original colour distribution for low mass haloes and that no significant determining properties are identified in massive haloes, suggesting modulations by additional stochastic processes in galaxy formation.

arXiv comment17 pages, 10 figures, published by MNRAS

References in corpus (73)

• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Determination of Cosmological Parameters
• Planck 2015 results. XIII. Cosmological parameters
• The Sloan Digital Sky Survey: Technical Summary
• Simulating the joint evolution of quasars, galaxies and their large-scale distribution
• The many lives of active galactic nuclei: cooling flows, black holes and the luminosities and colours of galaxies
• The EAGLE project: Simulating the evolution and assembly of galaxies and their environments
• Populating a cluster of galaxies - I. Results at z=0
• The broken hierarchy of galaxy formation
• Nine-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Final Maps and Results
• Introducing the Illustris Project: Simulating the coevolution of dark and visible matter in the Universe
• Simulating Galaxy Formation with the IllustrisTNG Model
• First results from the IllustrisTNG simulations: matter and galaxy clustering
• Color Separation of Galaxy Types in the Sloan Digital Sky Survey Imaging Data
• Quantifying the bimodal color-magnitude distribution of galaxies
• First results from the IllustrisTNG simulations: the galaxy color bimodality
• First results from the IllustrisTNG simulations: A tale of two elements -- chemical evolution of magnesium and europium
• From dwarf spheroidals to cDs: Simulating the galaxy population in a LCDM cosmology
• Simba: Cosmological Simulations with Black Hole Growth and Feedback
• First results from the IllustrisTNG simulations: radio haloes and magnetic fields
• Halo occupation numbers and galaxy bias
• The Halo Occupation Distribution: Towards an Empirical Determination of the Relation Between Galaxies and Mass
• Theoretical Models of the Halo Occupation Distribution: Separating Central and Satellite Galaxies
• The Luminosity and Color Dependence of the Galaxy Correlation Function
• Galaxy Clustering in the Completed SDSS Redshift Survey: The Dependence on Color and Luminosity
• Modeling Luminosity-Dependent Galaxy Clustering Through Cosmic Time
• The Broad-band Optical Properties of Galaxies with Redshifts 0.0 < z < 0.2
• How do galaxies populate Dark Matter halos?
• The bimodal galaxy color distribution: dependence on luminosity and environment
• Constraining Galaxy Formation and Cosmology with the Conditional Luminosity Function of Galaxies
• The Illustris Simulation: Public Data Release
• Chemical enrichment of the intra-cluster and intergalactic medium in a hierarchical galaxy formation model
• The Connection between Galaxies and Dark Matter Structures in the Local Universe
• Galaxy Groups in the SDSS DR4: II. halo occupation statistics
• Galaxy formation in WMAP1 and WMAP7 cosmologies
• Cosmological Constraints from a Combination of Galaxy Clustering and Lensing -- I. Theoretical Framework
• The DEEP2 Galaxy Redshift Survey: Color and Luminosity Dependence of Galaxy Clustering at z~1
• Dependence of Galaxy Quenching on Halo Mass and Distance from its Centre
• Halo Occupation Distribution Modeling of Clustering of Luminous Red Galaxies
• Galaxy Assembly Bias: A Significant Source of Systematic Error in the Galaxy-Halo Relationship
• The Dark Side of Galaxy Color
• Introducing Decorated HODs: modeling assembly bias in the galaxy-halo connection
• Halo Model at Its Best: Constraints on Conditional Luminosity Functions from Measured Galaxy Statistics
• Subhalo abundance matching and assembly bias in the EAGLE simulation
• The origin of scatter in the stellar mass - halo mass relation of central galaxies in the EAGLE simulation
• The VIMOS Public Extragalactic Redshift Survey (VIPERS): Galaxy segregation inside filaments at $z\simeq 0.7$
• Towards Cosmological Concordance on Galactic Scales
• The Impact of Assembly Bias on the Galaxy Content of Dark Matter Halos
• Semi-Analytic Galaxies - I. Synthesis of environmental and star-forming regulation mechanisms
• Halo assembly bias and the tidal anisotropy of the local halo environment
• The impact of assembly bias on the halo occupation in hydrodynamical simulations
• A Quantification of the Butterfly Effect in Cosmological Simulations and Implications for Galaxy Scaling Relations
• Mergers, Starbursts, and Quenching in the Simba Simulation
• Modelling galaxy clustering: halo occupation distribution versus subhalo matching
• Breaking the Degeneracies Between Cosmology and Galaxy Bias
• The Dark Side of Galaxy Color: evidence from new SDSS measurements of galaxy clustering and lensing
• Revealing the galaxy-halo connection in IllustrisTNG
• Dissecting and Modelling Galaxy Assembly Bias
• The Rise of Massive Red Galaxies: the color-magnitude and color-stellar mass diagrams for z < ~2 from the MUltiwavelength Survey by Yale-Chile (MUSYC)
• The evolution of the quenching of star formation in cluster galaxies since z $\sim$ 1
• Persistence of the Color-Density Relation and Efficient Environmental Quenching to $z\sim 1.4$
• Emulating galaxy clustering and galaxy-galaxy lensing into the deeply nonlinear regime: methodology, information, and forecasts
• A flexible subhalo abundance matching model for galaxy clustering in redshift space
• The impact of stellar feedback on hot gas in galaxy haloes: the Sunyaev-Zel'dovich effect and soft X-ray emission
• Extensions to models of the galaxy-halo connection
• The effects of assembly bias on cosmological inference from galaxy-galaxy lensing and galaxy clusters
• Baryons in the CosmicWeb of IllustrisTNG -- II: the Connection among Galaxies, Halos, their Formation Time and their Location in the Cosmic Web
• Quenching and morphological evolution due to circumgalactic gas expulsion in a simulated galaxy with a controlled assembly history
• The Conditional Colour-Magnitude Distribution: I. A Comprehensive Model of the Colour-Magnitude-Halo Mass Distribution of Present-Day Galaxies
• Galaxy assembly bias of central galaxies in the Illustris simulation
• Dependence of Halo Bias and Kinematics on Assembly Variables
• SHAM through the lens of a hydrodynamical simulation
• A general approach to quenching and galactic conformity
• Predicting halo occupation and galaxy assembly bias with machine learning