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arXiv · 0906.2810

The evolution of early and late type galaxies in the COSMOS up to z~1.2

Maurilio Pannella·Armin Gabasch·Yuliana Goranova·Niv Drory·Ulrich Hopp·Stefan Noll·Roberto P. Saglia·Veronica Strazzullo·Ralf Bender
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Abstract

The Cosmic Evolution Survey (COSMOS) allows for the first time a highly significant census of environments and structures up to redshift one, as well as a full morphological description of the galaxy population. In this paper we present a study aimed to constrain the evolution, in the redshift range 0.2 < z < 1.2, of the mass content of different morphological types and its dependence on the environmental density. We use a deep multicolor catalog, covering an area of ~0.7 square degrees inside the COSMOS field, with accurate photometric redshifts (i < 26.5 and dz/(z+1) ~ 0.035). We estimate galaxy stellar masses by fitting the multi-color photometry to a grid of composite stellar population models. We quantitatively describe the galaxy morphology by fitting PSF convolved Sersic profiles to the galaxy surface brightness distributions down to F814 = 24 mag for a sample of 41300 objects. We confirm an evolution of the morphological mix with redshift: the higher the redshift the more disk-dominated galaxies become important. We find that the morphological mix is a function of the local comoving density: the morphology density relation extends up to the highest redshift explored. The stellar mass function of disk-dominated galaxies is consistent with being constant with redshift. Conversely, the stellar mass function of bulge-dominated systems shows a decline in normalization with redshift. Such different behaviors of late-types and early-types stellar mass functions naturally set the redshift evolution of the transition mass. ABRIDGED

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Maurilio Pannella, Armin Gabasch, Yuliana Goranova, Niv Drory, Ulrich Hopp, Stefan Noll, Roberto P. Saglia, Veronica Strazzullo, Ralf Bender. 2009-06-15. The evolution of early and late type galaxies in the COSMOS up to z~1.2. https://doi.org/10.1088/0004-637x%2F701%2F1%2F787

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