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Assessing the galaxy population out to z ~ 2 using the Hubble Deep Field South

Theresa Wiegert·Duilia F. de Mello·Cathy Horellou
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Abstract

In this work we use the Hubble Deep Field South (HDF-S) version 2 images to assess the galaxy population out to z ~ 2. We have used two methods of templates fitting of the spectral energy distributions to obtain photometric redshifts and classify the objects. The Bayesian photometric redshifts gave better results when compared with 54 spectroscopic redshifts available in the literature. Analysis of the rest-frame colour distribution shows a bimodality out to z ~ 1.4. We separated our sample in a blue and a red population at B-V = 0.29. At low redshifts (0.2 0.29 whereas at higher redshifts ~ 60% of the galaxies are bluer than B-V < 0.29. Although in low numbers, a population of early-type galaxies (or heavily obscured low redshift galaxies) is seen out to z ~ 2.

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Theresa Wiegert, Duilia F. de Mello, Cathy Horellou. 2004-07-07. Assessing the galaxy population out to z ~ 2 using the Hubble Deep Field South. https://doi.org/10.1051/0004-6361%3A20041015

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