The evolution of KS-selected galaxies in the GOODS/CDFS deep ISAAC field

We present estimated redshifts and derived properties of a sample of 1663 galaxies with K-s <= 22 (Vega), selected from 50.4 arcmin(2) of the Great Observatories Origins Deep Survey/Chandra Deep Field South (GOODS/CDFS) field with deep Infrared Spectrometer and Array Camera (ISAAC) imaging, and make an extensive comparison of their properties with those of the extremely red galaxies (ERGs) selected in the same field. We study in detail the evolution of K-s-selected galaxies up to redshifts z similar to 4, and clarify the role of ERGs within the total K-s-band galaxy population. We compute the total K-s-band luminosity function (LF) and compare its evolution with the ERG LF. Up to < z(phot)> = 2.5, the bright end of the K-s-band LF shows no sign of decline, and is progressively well reproduced by the ERGs with increasing redshift. We also explore the evolution of massive systems present in our sample: up to 20-25 per cent of the population of local galaxies with assembled stellar mass M > 1 x 10(11) M-circle dot) has been formed before redshift z similar to 4, and contains similar to 45-70 per cent of the stellar mass density of the Universe at that redshift. Within our sample, the comoving number density of these massive systems is then essentially constant down to redshift z similar to 1.5, by which point most of them have apparently evolved into (I - K-s)-selected ERGs. The remaining massive systems observed in the local Universe are assembled later, at redshifts z <= 1.5. Our results therefore suggest a twofold assembly history for massive galaxies, in which galaxy/star formation proceeds very efficiently in high mass haloes at very high redshift.