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arXiv · 1206.3579

On the Shapes and Structures of High-Redshift Compact Galaxies

M. Chevance·A. Weijmans·I. Damjanov·R. G. Abraham·L. Simard·S. van den Bergh·E. Caris·K. Glazebrook
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Abstract

Recent deep Hubble Space Telescope WFC3 imaging suggests that a majority of compact quiescent massive galaxies at z~2 may contain disks. To investigate this claim, we have compared the ellipticity distribution of 31 carefully selected high-redshift massive quiescent compact galaxies to a set of mass-selected ellipticity and Sersic index distributions obtained from 2D structural fits to ~40,000$ nearby galaxies from the Sloan Digital Sky Survey. A Kolmogorov-Smirnov test shows that the distribution of ellipticities for the high-redshift galaxies is consistent with the ellipticity distribution of a similarly chosen sample of massive early-type galaxies. However the distribution of Sersic indices for the high-redshift sample is inconsistent with that of local early-type galaxies, and instead resembles that of local disk-dominated populations. The mismatch between the properties of high-redshift compact galaxies and those of both local early-type and disk-dominated systems leads us to conclude that the basic structures of high-redshift compact galaxies probably do not closely resemble those of any single local galaxy population. Any galaxy population analog to the high-redshift compact galaxies that exists at the current epoch is either a mix of different types of galaxies, or possibly a unique class of objects on their own.

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M. Chevance, A. Weijmans, I. Damjanov, R. G. Abraham, L. Simard, S. van den Bergh, E. Caris, K. Glazebrook. 2012-06-15. On the Shapes and Structures of High-Redshift Compact Galaxies. https://doi.org/10.1088/2041-8205%2F754%2F2%2Fl24

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