Galaxy Evolution in the Environment of ABCG 209

C. P. Haines; A. Mercurio; P. Merluzzi; F. La Barbera; M. Massarotti; G. Busarello; M. Girardi

doi:10.1051/0004-6361:20035841

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arXiv · astro-ph/0403556

Galaxy Evolution in the Environment of ABCG 209

C. P. Haines·A. Mercurio·P. Merluzzi·F. La Barbera·M. Massarotti·G. Busarello·M. Girardi

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Abstract

We examine the environmental effects on the photometric properties of galaxies for the rich galaxy cluster ABCG 209 at z=0.209. We use archive CFHT optical imaging of a 42'x28' field centred on the cluster to produce a galaxy sample complete to B=25.0 and R=24.5. Both the composite and red sequence galaxy luminosity functions are found to be dependent on the local galaxy surface density, their faint-end slopes becoming shallower with increasing density. We explain this as a combination of the morphology-density relation, and dwarf galaxies being cannibalised and/or disrupted by the cD galaxy and the ICM in the cluster core. The B-R colour of the red sequence itself appears 0.02mag redder for the highest-density regions, indicative of their stellar populations being marginally (<5%) older or (<20%) more metal-rich. This may be due to the galaxies themselves forming earliest in the rarest overdensities marked by rich clusters, or their star-formation being suppressed earliest by the ICM.

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C. P. Haines, A. Mercurio, P. Merluzzi, F. La Barbera, M. Massarotti, G. Busarello, M. Girardi. 2004-03-23. Galaxy Evolution in the Environment of ABCG 209. https://doi.org/10.1051/0004-6361%3A20035841

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