Superdense and normal early-type galaxies at 1<z<2
  We combined proprietary and archival HST observations to collect a sample of
62 early-type galaxies (ETGs) at 0.9<z<2 with spectroscopic confirmation of
their redshift and spectral type. The whole sample is covered by ACS or NICMOS
observations and partially by Spitzer and AKARI observations. We derived
morphological parameters by fitting their HST light profiles and physical
parameters by fitting their spectral energy distributions. The study of the
size-mass and the size-luminosity relations of these early-types shows that a
large fraction of them (~50) follows the local relations. These 'normal' ETGs
are not smaller than local counterparts with comparable mass. The remaining
half of the sample is composed of compact ETGs with sizes (densities) 2.5-3
(15-30) times smaller (higher) than local counterparts and, most importantly,
than the other normal ETGs at the same redshift and with the same stellar mass.
This suggests that normal and superdense ETGs at z~2 come from different
histories of mass assembly.
