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arXiv · 0707.2787

The Evolution of the Field and Cluster Morphology-Density Relation for Mass-Selected Samples of Galaxies

A. van der Wel·B. P. Holden·M. Franx·G. D. Illingworth·M. P. Postman·D. D. Kelson·I. Labbe·S. Wuyts·J. P. Blakeslee·H. C. Ford
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Abstract

The Sloan Digital Sky Survey (SDSS) and photometric/spectroscopic surveys in the GOODS-South field (the Chandra Deep Field-South, CDFS) are used to construct volume-limited, stellar mass-selected samples of galaxies at redshifts 0 2.5. The fraction of E+S0 galaxies is 43+/-3%$ at z~0.03 and 48+/-7% at z~0.8, i.e., it has not changed significantly since z~0.8. When combined with recent results for cluster galaxies in the same redshift range, we find that the morphology-density relation for galaxies more massive than 0.5M* has remained constant since at least z~0.8. This implies that galaxies evolve in mass, morphology and density such that the morphology-density relation does not change. In particular, the decline of star formation activity and the accompanying increase in the stellar mass density of red galaxies since z~1 must happen without large changes in the early-type galaxy fraction in a given environment.

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A. van der Wel, B. P. Holden, M. Franx, G. D. Illingworth, M. P. Postman, D. D. Kelson, I. Labbe, S. Wuyts, J. P. Blakeslee, H. C. Ford. 2007-11-01. The Evolution of the Field and Cluster Morphology-Density Relation for Mass-Selected Samples of Galaxies. https://doi.org/10.1086/521783

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