Properties of High Redshift Cluster Ellipticals

Mark Dickinson

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arXiv · astro-ph/9703035

Properties of High Redshift Cluster Ellipticals

Mark Dickinson

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Abstract

Cluster ellipticals are often thought to be among the oldest galaxies in the universe, with the bulk of their stellar mass formed at early cosmic epochs. I review recent observations of color evolution in early-type cluster galaxies at high redshift, which show remarkably little change in the color-magnitude relation out to z = 1. Spectra of elliptical galaxies from 1.15 < z < 1.41 demonstrate the presence of a dominant old stellar population even at these large lookback times, although there is some evidence for a tail of later star formation. The Kormendy relation, a photometric/morphological scaling law for elliptical galaxies, is used to extend fundamental plane investigations to z = 1.2 and to test for luminosity evolution. While the evidence, overall, is consistent with simple and mild passive evolution, I review some caveats and briefly consider the data in the light of hierarchical galaxy formation models.

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Mark Dickinson. 1997-03-06. Properties of High Redshift Cluster Ellipticals. https://arxiv.org/abs/astro-ph/9703035

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