Ages and Metallicities of Hickson Compact Group Galaxies

Abstract

Hickson Compact Groups (HCGs) constitute an interesting extreme in the range of environments in which galaxies are located, as the space density of galaxies in these small groups are otherwise only found in the centres of much larger clusters. The work presented here uses Lick indices to make a comparison of ages and chemical compositions of galaxies in HCGs with those in other environments (clusters, loose groups and the field). The metallicity and relative abundance of `$\alpha$-elements' show strong correlations with galaxy age and central velocity dispersion, with similar trends found in all environments. However, we show that the previously reported correlation between $\alpha$-element abundance ratios and velocity dispersion disappears when a full account is taken of the the abundance ratio pattern in the calibration stars. This correlation is thus found to be an artifact of incomplete calibration to the Lick system. Variations are seen in the ranges and average values of age, metallicity and $\alpha$-element abundance ratios for galaxies in different environments. Age distributions support the hierarchical formation prediction that field galaxies are on average younger than their cluster counterparts. However, the ages of HCG galaxies are shown to be more similar to those of cluster galaxies than those in the field, contrary to the expectations of current hierarchical models. A trend for lower velocity dispersion galaxies to be younger was also seen. This is again inconsistent with hierarchical collapse models, but is qualitatively consistent with the latest N-body-SPH models based on monolithic collapse in which star formation continues for many Gyr in low mass halos.

arXiv comment18 pages. Submitted for publication in MNRAS

References in corpus (26)

• Stellar population models of Lick indices with variable element abundance ratios
• The Stellar Population Histories of Early-Type Galaxies. II. Controlling Parameters of the Stellar Populations
• The Properties of Poor Groups of Galaxies: I. Spectroscopic Survey and Results
• Evolution of the Hubble Sequence in Hierarchical Models for Galaxy Formation
• The Ages of Elliptical Galaxies in a Merger Model
• A ROSAT survey of Hickson's compact galaxy groups
• Spatially resolved spectroscopy of Coma cluster early -- type galaxies: III. The stellar population gradients
• GCD+: A New Chemodynamical Approach to Modeling SNe and Chemical Enrichment
• A Catalogue and Analysis of Local Galaxy Ages and Metallicities
• Star formation histories of early-type galaxies. I: Higher order Balmer lines as age indicators
• A comparison of stellar populations in galaxy populations across a wide range of Hubble types
• Photo-Chemical Evolution of Elliptical Galaxies I. The high-redshift formation scenario
• On the dependence of spectroscopic indices of early-type galaxies on age, metallicity and velocity dispersion
• Chemical Enrichment and the Origin of the Colour-Magnitude Relation of Elliptical Galaxies in a Hierarchical Merger Model
• Abundances in metal-rich stars - Detailed abundance analysis of 47 G and K dwarf stars with [Me/H] $>$ 0.10 dex
• Cluster vs. Field Elliptical Galaxies and Clues on their Formation
• A photometric and spectroscopic study of dwarf and giant galaxies in the Coma cluster -- III. Spectral ages and metallicities
• Early-type galaxies in low-density environments
• Effects of Interaction Induced Activities in Hickson Compact Groups: CO and FIR Study
• Evolution of Compact Groups of Galaxies I. Merging Rates
• Stellar populations of cluster E and S0 galaxies
• Physically Detached "Compact Groups"
• Effects of SNe II and SNe Ia Feedback on the Chemo-Dynamical Evolution of Elliptical Galaxies
• Small Groups of Galaxies: a Clue to a Critical Universe
• The Nature of the Activity in Hickson Compact Groups of Galaxies
• On The Relationship Between Age and Dynamics in Elliptical Galaxies

Cited by in corpus (73)

• The epochs of early-type galaxy formation as a function of environment
• The formation history of elliptical galaxies
• Galaxy Pairs in the Sloan Digital Sky Survey I: Star Formation, AGN Fraction, and the Luminosity/Mass-Metallicity Relation
• Environment and self-regulation in galaxy formation
• NOAO Fundamental Plane Survey -- II. Age and Metallicity along the Red Sequence
• Stellar populations of early-type galaxies in different environments II. Ages and metallicities
• Flux-calibrated stellar population models of Lick absorption-line indices with variable element abundance ratios
• Colors, magnitudes and velocity dispersions in early-type galaxies: Implications for galaxy ages and metallicities
• Star formation history of barred disc galaxies
• Spatially resolved spectroscopy of early-type galaxies over a range in mass
• Early-type galaxies at large galactocentric radii - II. Metallicity gradients, and the [Z/H]--mass, [alpha/Fe]--mass relations
• The abundance of ultra-diffuse galaxies from groups to clusters: UDGs are relatively more common in more massive haloes
• Stellar populations of early-type galaxies in different environments I. Line-strength indices
• The metal enrichment of elliptical galaxies in hierarchical galaxy formation models
• A Robust Method for the Analysis of Integrated Spectra from Globular Clusters using Lick Indices
• The Chemical Properties of Milky Way and M31 Globular Clusters: I. A Comparative Study
• Chemical evolution of local galaxies in a hierarchical model
• Spatially resolved kinematics and stellar populations of brightest cluster and group galaxies
• The connection between globular cluster systems and their host galaxy and environment: a case study of the isolated elliptical NGC 821
• The luminosity function of the fossil group RX J1552.2+2013
• X-ray Properties of Young Early Type Galaxies: I. X-ray Luminosity Function of LMXBs
• The NOAO Fundamental Plane Survey - III. Variations in the stellar populations of red-sequence galaxies from the cluster core to the virial radius
• On the Nature of Fossil Galaxy Groups: Are they really fossils ?
• Line Strengths in Early-Type Cluster Galaxies at z=0.33: Implications for alpha/Fe, Nitrogen and the Histories of E/S0s
• The Age, Metallicity and Alpha-Element Abundance of Galactic Globular Clusters from Single Stellar Population Models
• The Chemical Properties of Milky Way and M31 Globular Clusters: II. Stellar Population Model Predictions
• Generalisations of the Tully-Fisher relation for early and late-type galaxies
• Stellar Populations in Nearby Lenticular Galaxies
• The spatially resolved stellar populations of isolated early-type galaxies
• The fundamental plane of isolated early-type galaxies
• A Principal Component Analysis approach to the Star Formation History of elliptical galaxies in Compact Groups
• Truncated Star Formation in Compact Groups of Galaxies: A Stellar Population Study
• Ages, metallicities and $\alpha$-element enhancement for galaxies in Hickson compact groups
• Spatially resolved stellar populations in the isolated elliptical NGC 821
• The early-type galaxies NGC 1407 and NGC 1400 - II: star formation and chemical evolutionary history
• The history of star formation and mass assembly in early-type galaxies
• Colours of Bulges and Discs within Galaxy Clusters and the Signature of Disc Fading on Infall
• Where are compact groups in the local Universe?
• VEGAS: A VST Early-type GAlaxy Survey.VI. The diffuse light in HCG 86 from the ultra-deep VEGAS images
• Age and metallicity gradients in fossil ellipticals
• X-ray observations of three young, early-type galaxies
• A Catalog of Distant Compact Groups Using DPOSS
• Compact groups in theory and practice -- IV. The connection to large-scale structure
• Massive elliptical galaxies in X-rays: the role of late gas accretion
• Seyfert's Sextet: A Slowly Dissolving Stephan's Quintet?
• The star formation histories of Hickson compact group galaxies
• A Principal Components Analysis of the Lick Indices of Galactic Globular Clusters
• The stellar populations of early-type galaxies -- II. The effects of environment and mass
• Uncovering the formation of ultra-compact dwarf galaxies by multivariate statistical analysis
• Keck spectroscopy of globular clusters in the spiral galaxy NGC 2683
• The effects of stellar populations on galaxy scaling relations in the 6dF Galaxy Survey
• Nature vs. nurture in the low-density environment: structure and evolution of early-type dwarf galaxies in poor groups
• Faint Dwarf Galaxies in Hickson Compact Group 90
• Ages of Elliptical Galaxies: Single versus Multi Population Interpretation
• Fossil group origins IX. Probing the formation of fossil galaxy groups with stellar population gradients of their central galaxies
• The Fastest Galaxy Evolution in an Unbiased Compact Group Sample with WISE
• Early-Type Galaxy Star Formation Histories in Different Environments
• Kinematic Properties and Stellar Populations of Faint Early-Type Galaxies: II. Line-Strength Measurements of Central Coma Galaxies
• The elliptical galaxies NGC 1052 and NGC 7796: stellar populations and abundance alpha/Fe ratio
• The DPOSS II compact group survey: first spectroscopically confirmed candidates
• Comparing galaxy populations in compact and loose groups of galaxies III. Effects of environment on star formation
• Exploring X-ray Binary Populations in Compact Group Galaxies with $Chandra$
• Probing Spectral Line Gradients Beyond One Effective Radius in NGC 3610
• Interpreting the galaxy group CG J1720-67.8 through evolutionary synthesis models
• Physical and kinematic conditions of the local merging galaxy NGC 1487
• Age and Metallicity of galaxies in different environments of the Coma supercluster
• Optical properties of the NGC 5328 group of galaxies
• The Occurrence of Compact Groups of Galaxies Through Cosmic Time
• Stellar Population Properties of ETGs in Compact Groups of Galaxies
• Cosmic Pathways for Compact Groups in the Milli-Millennium Simulation
• Compact groups of galaxies in GAMA -- Probing the densest minor systems at intermediate redshifts
• The impact of binary star yields on the spectra of galaxies
• Star Formation Histories of Nearby Elliptical Galaxies. II. Merger Remnant Sample