The evolution of galaxy sizes
Abstract
We present a study of galaxy sizes in the local Universe as a function of galaxy environment, comparing clusters and the general field. Galaxies with radii and masses comparable to high-z massive and compact galaxies represent 4.4% of all galaxies more massive than 3 X 10^{10} M_sun in the field. Such galaxies are 3 times more frequent in clusters than in the field. Most of them are early-type galaxies with intermediate to old stellar populations. There is a trend of smaller radii for older luminosity-weighted ages at fixed galaxy mass. We show the relation between size and luminosity-weighted age for galaxies of different stellar masses and in different environments. We compare with high-z data to quantify the evolution of galaxy sizes. We find that, once the progenitor bias due to the relation between galaxy size and stellar age is removed, the average amount of size evolution of individual galaxies between high- and low-z is mild, of the order of a factor 1.6.
Cite
@article{arxiv.1212.3207,
title = {The evolution of galaxy sizes},
author = {Bianca M. Poggianti and Rosa Calvi and Daniele Bindoni and Mauro D'Onofrio and Alessia Moretti and Tiziano Valentinuzzi and Giovanni Fasano and Jacopo Fritz and Gabriella De Lucia and Benedetta Vulcani and Daniela Bettoni and Marco Gullieuszik and Alessandro Omizzolo},
journal= {arXiv preprint arXiv:1212.3207},
year = {2015}
}
Comments
to appear in the proceedings of the IAU S295: The intriguing life of massive galaxies, editors D. Thomas, A. Pasquali & I. Ferreras