Submm-bright QSOs at z~2: signposts of co-evolution at high z
  We have assembled a sample of 5 X-ray and submm-luminous z~2 QSOs which are
therefore both growing their central black holes through accretion and forming
stars copiously at a critical epoch. Hence, they are good laboratories to
investigate the co-evolution of star formation and AGN. We have performed a
preliminary analysis of the AGN and SF contributions to their UV-to-FIR SEDs,
fitting them with simple direct (disk), reprocessed (torus) and star formation
components. All three are required by the data and hence we confirm that these
objects are undergoing strong star formation in their host galaxies at rates
500-2000 Msun/y. Estimates of their covering factors are between about 30 and
90%. In the future, we will assess the dependence of these results on the
particular models used for the components and relate their observed properties
to the intrinsice of the central engine and the SF material, as well as their
relevance for AGN-galaxy coevolution.
