Cambridge University Press (CUP), Proceedings of the International Astronomical Union, S245(3), p. 59-62, 2007
DOI: 10.1017/s1743921308017286
Full text: Unavailable
AbstractThe Sloan Digital Sky Survey (SDSS) and photometric/spectroscopic surveys of two z ~ 0.8 massive clusters of galaxies and the Chandra Deep Field-South (CDFS) are used to construct volume-limited, stellar mass-selected samples of galaxies at redshifts 0 < z < 1 in a large range of environments. Morphologies are determined visually and with an automated method, using the Sérsic parameter n and a measure of the residual from the Sérsic model fits, called “bumpiness”, to distinguish different morphologies. The agreement between the visual and automated methods is excellent. The fraction of E+S0 galaxies with masses larger than ~ 0.5 M* is 40 − 50% in the field, and > 80% in the clusters, without significant changes with redshift. Therefore, we find that the morphology-density relation (MDR) for galaxies more massive than ~ 0.5 M* has remained constant since at least z ~ 0.8. This implies that galaxy evolution (in terms of mass, star formation, color, morphology, etc.) must happen such that the MDR does not change.