Both in the present-day Universe and earlier on, approximately z~3, we have documented profound structural differences between star-forming and quiescent galaxies. The former host their star formation in rotating disks (thinner and colder today, apparently thicker and hotter at high redshifts), the latter are predominantly dynamically hot systems and have spheroidal morphology, At high redshift (z>1) and up to when quiescent systems can be reliably identified (z~3-4), dynamical information becomes more uncertain, at least in passive systems, but this dichotomy seems to persist at least morphologically. Therecent discovery that disks at high redshift (22) have mostly focused on the growth of the core stellar mass density, e.g. at r<1 kpc. These very central volumes are the sink of all the dissipative processes that take place during star formation and while they inform us, in an integral way, on the accretion history of the galaxy of both the dissipative (gas, via cold and hot accretion) and non-dissipative (stars and dark matter, via adiabatic contractions) components, they are baryon-dominated even in today disks and do not contain information on if and how the large-scale structure of galaxies evolves, dark matter included. Here I show novel evidence that the large-scale spatial distribution of stellar mass (from rest-frame light at ~4000 to 6400 Ang), i.e. of one of the two non-dissipative components, of massive galaxies at 1.5
Local scientific contact: E. Daddi