Globular cluster systems in elliptical galaxies of Coma

Abstract

Globular cluster systems of 17 elliptical galaxies have been studied in the Coma cluster of galaxies. Surface-brightness fluctuations have been used to determine total populations of globular clusters and specific frequency (S_N) has been evaluated for each individual galaxy. Enormous differences in S_N between similar galaxies are found. In particular, S_N results vary by an order of magnitude from galaxy to galaxy. Extreme cases are the following: a) at the lower end of the range, NGC 4673 has S_N = 1.0 +/- 0.4, a surprising value for an elliptical galaxy, but typical for spiral and irregular galaxies; b) at the upper extreme, MCG +5 -31 -063 has S_N = 13.0 +/- 4.2 and IC 4051 S_N = 12.7 +/- 3.2, and are more likely to belong to supergiant cD galaxies than to "normal" elliptical galaxies. Furthermore, NGC 4874, the central supergiant cD galaxy of the Coma cluster, also exhibits a relatively high specific frequency (S_N = 9.0 +/- 2.2). The other galaxies studied have S_N in the range [2, 7], the mean value being S_N = 5.1. No single scenario seems to account for the observed specific frequencies, so the history of each galaxy must be deduced individually by suitably combining the different models (in situ, mergers, and accretions). The possibility that Coma is formed by several subgroups is also considered. If only the galaxies of the main subgroup defined by Gurzadyan & Mazure (2001) are used, a trend in S_N arises in the sense of S_N being bigger in higher density regions. This result needs further confirmation.

43 pages including 12 .ps figures, accepted for publication in ApJ

References in corpus (3)

• The SBF Survey of Galaxy Distances. IV. SBF Magnitudes, Colors, and Distances
• The Infrared Surface Brightness Fluctuation Hubble Constant
• Galaxy Associations within the Coma Cluster

Cited by in corpus (20)

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• Dark Matter Halos in Galaxies and Globular Cluster Populations. II: Metallicity and Morphology
• The HST/ACS Coma Cluster Survey: I - Survey Objectives and Design
• Globular Cluster Systems in Brightest Cluster Galaxies. III: Beyond Bimodality
• Quantitative Morphology of Galaxies in the Core of the Coma Cluster
• The Globular Cluster Systems in the Coma Ellipticals. IV: WFPC2 Photometry for Five Giant Ellipticals
• Ultra-Compact Dwarfs in the Coma Cluster
• Hubble Space Telescope Observations of cD Galaxies and their Globular Cluster Systems
• A Point Source Excess in Abell 1185: Intergalactic Globular Clusters?
• The r'-band luminosity function of Abell1367: a comparison with Coma
• The Globular Cluster System of the Coma cD Galaxy NGC 4874 from Hubble Space Telescope ACS and WFC3/IR Imaging
• The extremely populated globular cluster system of the lenticular galaxy NGC 6861
• The Galaxy Luminosity Functions down to M_R=-10 in the Coma Cluster
• Intergalactic globular clusters and the faint end of the galaxy number counts in A1656 (Coma)
• Statistical analysis of dwarf galaxies and their globular clusters in the Local Volume
• Galaxy And Mass Assembly (GAMA): $\mathbf{z}\sim 0$ Galaxy Luminosity Function down to $\mathbf{L}\sim 10^6{\mathbf{L}}_{\odot }$ via Clustering Based Redshift Inference
• Globular Clusters in NGC 4839 Falling into Coma: Evidence for the Second Infall?
• Beyond the Hubble Deep Field Limiting Magnitude: Faint Galaxy Number Counts from Surface-Brightness Fluctuations
• Evidence for Environmental Stripping in the Coma Cluster