Galaxy populations in the Antlia cluster. I. Photometric properties of early-type galaxies

Abstract

We present the first colour-magnitude relation (CMR) of early-type galaxies in the central region of the Antlia cluster, obtained from CCD wide-field photometry in the Washington photometric system. Integrated (C -T1) colours, T1 magnitudes, and effective radii have been measured for 93 galaxies (i.e. the largest galaxies sample in the Washington system till now) from the FS90 catalogue (Ferguson & Sandage 1990). Membership of 37 objects can be confirmed through new radial velocities and data collected from the literature. The resulting colour-magnitude diagram shows that early-type FS90 galaxies that are spectroscopically confirmed Antlia members or that were considered as definite members by FS90, follow a well defined CMR (sigma_(C -T1) ~ 0.07 mag) that spans 9 magnitudes in brightness with no apparent change of slope. This relation is very tight for the whole magnitude range but S0 galaxies show a larger dispersion, apparently due to a separation of ellipticals and S0s. Antlia displays a slope of -13.6 in a T1 vs. (C -T1) diagram, in agreement with results for clusters like Fornax, Virgo, Perseus and Coma, which are dynamically different to Antlia. This fact might indicate that the build up of the CMR in cluster of galaxies is more related to galaxies internal processes than to the influence of the environment. Interpreting the CMR as a luminosity-metallicity relation of old stellar systems, the metallicities of the Antlia galaxies define a global relation down to Mv ~ -13. We also find, for early-type dwarfs, no clear relation between luminosity and effective radius, indicating a nearly constant mean effective radius of ~ 1 kpc. This value is also found in several samples of dwarf galaxies in Virgo and Coma.

13 pages, 6 figures. Accepted for publication in MNRAS

References in corpus (12)

• Empirical Color Transformations Between SDSS Photometry and Other Photometric Systems
• A Possible Origin of the Mass-Metallicity Relation of Galaxies
• Virgo cluster early-type dwarf galaxies with the Sloan Digital Sky Survey. II. Early-type dwarfs with central star formation
• Virgo cluster early-type dwarf galaxies with the Sloan Digital Sky Survey. IV. The color-magnitude relation
• Keck spectroscopy of the faint dwarf elliptical galaxy population in the Perseus Cluster core: mixed stellar populations and a flat luminosity function
• A Quantitative Link Between Globular Clusters and the Stellar Halos in Elliptical Galaxies
• Color-Magnitude Diagrams of Resolved Stars in Virgo Cluster Dwarf Galaxies
• A deep wide survey of faint low surface brightness galaxies in the direction of the Coma cluster of galaxies
• New evidence for a linear colour-magnitude relation and a single Schechter function for red galaxies in a nearby cluster of galaxies down to M*+8
• Discovery of a new M32-like "Compact Elliptical" galaxy in the halo of the Abell 496 cD galaxy
• The Dwarf Galaxy Population in Nearby Groups. The data
• Formation and Evolution of Dwarf Elliptical Galaxies

Cited by in corpus (13)

• On the origin of the faint-end of the red sequence in high density environments
• ELVES I: Structures of Dwarf Satellites of MW-like Galaxies; Morphology, Scaling Relations, and Intrinsic Shapes
• The origin of the mu_e - M_B and Kormendy relations in dwarf elliptical galaxies
• Hubble Space Telescope Survey of the Perseus Cluster: II. Photometric scaling relations in different environments
• Galaxy populations in the Antlia cluster. II. Compact elliptical galaxy candidates
• Numerical simulations of dwarf galaxy merger trees
• Redshift determination of the BL Lac object 3C66A by the detection of its host galaxy cluster at $z=0.340$
• Isolated elliptical galaxies and their globular cluster systems. II. NGC 7796 - globular clusters, dynamics, companion
• Beyond Ultra-diffuse Galaxies. I. Mass--Size Outliers among the Satellites of Milky Way Analogs
• Ultra-Compact Dwarfs around NGC 3268
• The Nature of Low Surface Brightness Galaxies in the Hyper Suprime-Cam Survey
• Early-type galaxies in the Antlia Cluster: global properties
• Searching for star-forming dwarf galaxies in the Antlia cluster