Evidence for the rapid formation of low mass early-type galaxies in dense environments

Abstract

We explore the environmental dependence of star formation timescales in low mass galaxies using the [$\alpha$/Fe] abundance ratio as an evolutionary clock. We present integrated [$\alpha$/Fe] measurements for 11 low mass ($M_{\star }\sim 10^9{M}_{\odot }$) early-type galaxies (ETGs) with a large range of cluster-centric distance in the Virgo Cluster. We find a gradient in [$\alpha$/Fe], where the galaxies closest to the cluster center (the cD galaxy, M87) have the highest values. This trend is driven by galaxies within a projected radius of 0.4~Mpc (0.26 times the virial radius of Virgo~A), all of which have super-solar [$\alpha$/Fe]. Galaxies in this mass range exhibit a large scatter in the [$\alpha$/Fe]--$\sigma$ diagram, and do not obviously lie on an extension of the relation defined by massive ETGs. In addition, we find a correlation between [$\alpha$/Fe] and globular cluster specific frequency ($S_N$), suggesting that low-mass ETGs that formed their stars over a short period of time, were also efficient at forming massive star clusters. The innermost low-mass ETGs in our sample have [$\alpha$/Fe] values comparable to that of M87, implying that environment is the controlling factor for star formation timescales in dense regions. These low-mass galaxies could be the surviving counterparts of the objects that have already been accreted into the halo of M87, and may be the link between present-day low-mass galaxies and the old, metal-poor, high-[$\alpha$/Fe], high-$S_N$ stellar populations seen in the outer halos of massive ETGs.

11 pages, 8 figures

References in corpus (22)

• The ACS Virgo Cluster Survey. VIII. The Nuclei of Early-Type Galaxies
• The Atlas3D Project - XXX. Star formation histories and stellar population scaling relations of early-type galaxies
• The ACS Virgo Cluster Survey XV. The Formation Efficiencies of Globular Clusters in Early-Type Galaxies: The Effects of Mass and Environment
• Population Synthesis in the Blue IV: Accurate Model Predictions for Lick Indices and UBV Colors in Single Stellar Populations
• The ACS Virgo Cluster Survey. XII. The Luminosity Function of Globular Clusters in Early Type Galaxies
• On the Star Formation Rate - Brightest Cluster Relation: Estimating the peak SFR in post-merger galaxies
• Virgo cluster early-type dwarf galaxies with the Sloan Digital Sky Survey. I. On the possible disk nature of bright early-type dwarfs
• Globular cluster formation in the context of galaxy formation and evolution
• Dark Matter Halos in Galaxies and Globular Cluster Populations
• Evolution of dwarf early-type galaxies I. Spatially resolved stellar populations and internal kinematics of Virgo cluster dE/dS0 galaxies
• Modeling the Formation of Globular Cluster Systems in the Virgo Cluster
• A spectroscopic survey of dwarf galaxies in the Coma Cluster: Stellar populations, environment and downsizing
• The relation between stellar populations, structure and environment for dwarf elliptical galaxies from the MAGPOP-ITP
• On the Assembly of Dwarf Galaxies in Clusters and their Efficient Formation of Globular Clusters
• Stellar Kinematics and Structural Properties of Virgo Cluster Dwarf Early-Type Galaxies from the SMAKCED Project III. Rotation versus Pressure Support
• The reversal of the SF-density relation in a massive, X-ray selected galaxy cluster at z=1.58: results from Herschel
• Stellar Kinematics and Structural Properties of Virgo Cluster Dwarf Early-Type Galaxies from the SMAKCED Project II. The Survey and a Systematic Analysis of Kinematic Anomalies and Asymmetries
• The Next Generation Virgo Cluster Survey. XII. Stellar Populations and Kinematics of Compact, Low-Mass Early-Type Galaxies from Gemini GMOS-IFU Spectroscopy
• Kinematics and Stellar Populations of Low-Luminosity Early-Type Galaxies in the Abell 496 Cluster
• Virgo Cluster and field dwarf ellipticals in 3D - II. Internal dynamics points to tidal harassment?
• On the Reversal of SFR-Density Relation at z=1: Insights from Simulations
• Lick-index entanglement and biased diagnostic of stellar populations in galaxies

Cited by in corpus (32)

• The Next Generation Virgo Cluster Survey. XXIII. Fundamentals of nuclear star clusters over seven decades in galaxy mass
• The Globular Cluster Systems of Ultra-Diffuse Galaxies in the Coma Cluster
• The Next Generation Virgo Cluster Survey (NGVS). XXX. Ultra-Diffuse Galaxies and their Globular Cluster Systems
• A Rich Globular Cluster System in Dragonfly 17: Are Ultra-Diffuse Galaxies Pure Stellar Halos?
• Low Metallicities and Old Ages for Three Ultra-Diffuse Galaxies in the Coma Cluster
• ELVES II: GCs and Nuclear Star Clusters of Dwarf Galaxies; The Importance of Environment
• The Stellar Populations of Two Ultra-Diffuse Galaxies from Optical and Near-infrared Photometry
• The SAMI Galaxy Survey: stellar population and structural trends across the Fundamental Plane
• The MAGPI Survey -- science goals, design, observing strategy, early results and theoretical framework
• The ACS Fornax Cluster Survey. III. Globular Cluster Specific Frequencies of Early-Type Galaxies
• The MASSIVE Survey - XII Connecting Stellar Populations of Early-Type Galaxies to Kinematics and Environment
• The Next Generation Virgo Cluster Survey (NGVS) XXXI. The kinematics of intra-cluster globular clusters in the core of the Virgo cluster
• Specific Frequencies and Luminosity Profiles of Cluster Galaxies and Intracluster Light in Abell 1689
• How nucleation and luminosity shape faint dwarf galaxies
• Gravitational Potential and Surface Density Drive Stellar Populations -- II. Star-Forming Galaxies
• Simulating the Spatial Distribution and Kinematics of Globular Clusters within Galaxy Clusters in Illustris
• Stellar Population Properties of Ultracompact Dwarfs in M87: a Mass-metallicity Correlation Connecting Low-metallicity Globular Clusters and Compact Ellipticals
• Spatially Resolved Stellar Spectroscopy of the Ultra-diffuse Galaxy Dragonfly 44. III. Evidence for an Unexpected Star-Formation History
• Young, metal-enriched cores in early-type dwarf galaxies in the Virgo cluster based on colour gradients
• The formation of early-type galaxies through monolithic collapse of gas clouds in Milgromian gravity
• Globular Clusters As Tracers of Fine Structure in the Dramatic Shell Galaxy NGC 474
• Black holes as the source of dark energy: a stringent test with high-redshift JWST AGNs
• The SAMI-Fornax Dwarfs Survey III: Evolution of [$\alpha$/Fe] in dwarfs, from Galaxy Clusters to the Local Group
• SDSS-IV MaNGA: Environmental dependence of the Mgb/<Fe>-sigma_* relation for nearby galaxies
• Coordinated Assembly of Brightest Cluster Galaxies
• On the accretion of a new group of galaxies onto Virgo: II. The effect of pre-processing on the stellar population content of dEs
• The Influence of Environment on the Chemical Evolution in Low-mass Galaxies
• The Next Generation Virgo Cluster Survey. XXXIII. Stellar Population Gradients in the Virgo Cluster Core Globular Cluster System
• The Color Gradients of the Globular Cluster Systems in M87 and M49
• The star formation timescale of elliptical galaxies -- Fitting [Mg/Fe] and total metallicity simultaneously
• Scaling relations of early-type galaxies in MOND
• Growth of black holes at the centre of early-type galaxies in MOND