Restrictions to the galaxy evolutionary models from the Hawaiian Deep Fields SSA13 and SSA22

J. A. L. Aguerri; I. Trujillo

doi:10.1046/j.1365-8711.2002.05446.x

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Restrictions to the galaxy evolutionary models from the Hawaiian Deep Fields SSA13 and SSA22

J. A. L. Aguerri·I. Trujillo

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Abstract

Quantitative structural analysis of the galaxies present in the Hawaiian Deep Fields SSA13 and SSA22 is reported. The structural parameters of the galaxies have been obtained automatically by fitting a two-component model (Sersic r^{1/n} bulge and exponential disc) to the surface brightness of the galaxies. The galaxies were classified on the basis of the bulge-to-total luminosity ratio (B/T). The magnitude selection criteria and the reliability of our method have been checked by using Monte Carlo simulations. A complete sample of objects up to redshift 0.8 has been achieved. Spheroidal objects (E/S0) represent ~33% and spirals ~41% of the total number of galaxies, while mergers and unclassified objects represent ~26%. We have computed the comoving space density of the different kinds of objects. In an Einstein-de Sitter universe a decrease in the comoving density of E/S0 galaxies is observed as redshift increases (a ~30% less at z=0.8), while for spiral galaxies a relatively quiet evolution is reported. The framework of hierarchical clustering evolution models of galaxies seems to be the most appropriate to explain our results.

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J. A. L. Aguerri, I. Trujillo. 2002-02-22. Restrictions to the galaxy evolutionary models from the Hawaiian Deep Fields SSA13 and SSA22. https://doi.org/10.1046/j.1365-8711.2002.05446.x

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