Scientific Seminars

High redshift massive galaxies: the SWIRE view

Stefano Berta
MPE

2008-12-04    14:00    IASF - Sala riunioni

Despite the recent extraordinary progress in observational cosmology and the successful convergence on a single cosmological model, galaxy formation and evolution largely remain an open issue. One critical aspect is how and when the present-day most massive galaxies (i.e. M>=10^11 Msun) were built up and what type of evolution characterized their growth over cosmic time. According to the most successful theoretical models, the formation of galaxies and large scale structure occurs in the frame of some variant of "biased" hierarchical buildup within a Lambda-CDM cosmology. In these scenarios the most massive objects (e.g. M > several 10^11 Msun) are predicted to assemble earlier, more quickly and in richer environments than less massive ones. A direct observational mapping of galaxy evolution through cosmic time is thus particularly important and rewarding, especially if a significant number of massive galaxies at 110^14) dark matter haloes, which are predicted the most massive galaxies. We are carrying out a systematic search for massive (M>10^11 Msun) galaxies at redshift z=2-3 in the SWIRE ELAIS-S1 field. I will present here the first results obtained in the central square degree of this area for the class of IR-peakers, highlighting their importance in understanding the mass downsizing effect.