Disk galaxies at z=2 in OWLS
  We use the OWLS (OverWhelmingly Large Simulations) set of cosmological
Nbody/gasdynamical simulations to study the properties of simulated galaxies at
z=2. We focus on the effect of supernova feedback from evolving stars on the
baryonic mass and angular momentum content of galaxies that assemble at the
center of 1e11-3e12 h^{-1}M_\odot halos. Our main finding is that the mass and
angular momentum of such galaxies are strongly coupled, in a way that is
approximately independent of feedback: varying the feedback implementation
leads, in a given halo, to large variations in galaxy mass but leaves the
galaxy mass-angular momentum correlation largely unaltered. In particular, the
ratio between the angular momentum of a galaxy and that of its surrounding halo
(j_d=J_gal/J_vir) correlates closely with the galaxy mass (expressed in units
of the virial mass of the halo; m_d=M_gal/M_vir). This correlation differs
substantially from the m_d=j_d assumption commonly adopted in semianalytic
models of galaxy formation. We use these results to infer the sizes of disk
galaxies at z=2 expected in the LCDM scenario and to interpret recent
observations of extended disks at z~2 by the SINS collaboration
