Disk galaxy evolution: from the Milky Way to high-redshift disks

Abstract

We develop a detailed model of the Milky Way (a ``prototypical'' disk galaxy) and extend it to other disks with the help of some simple scaling relations, obtained in the framework of Cold Dark Matter models. This phenomenological (``hybrid'') approach to the study of disk galaxy evolution allows us to reproduce successfully a large number of observed properties of disk galaxies in the local Universe and up to redshift z~1. The important conclusion is that, on average, massive disks have formed the bulk of their stars earlier than their lower mass counterparts: the ``star formation hierarchy'' has been apparently opposite to the ``dark matter assembly'' hierarchy. It is not yet clear whether ``feedback'' (as used in semi-analytical models of galaxy evolution) can explain that discrepancy.