Astrophys. J., 743, 146 (2011/December-3)
Active and passive galaxies at z ∼ 2: rest-frame optical morphologies with WFC3.
CAMERON E., CAROLLO C.M., OESCH P.A., BOUWENS R.J., ILLINGWORTH G.D., TRENTI M., LABBE I. and MAGEE D.
Abstract (from CDS):
We use the high angular resolution in the near-infrared of the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope to determine YHVz color-color-selection criteria to identify and characterize 1.5 < z < 3.5 galaxies in the Hubble Ultra Deep Field 2009 (HUDF09) and Early Release Science (GOODS-South) fields. The WFC3 NIR images reveal galaxies at these redshifts that were undetected in the rest-frame UV HUDF/GOODS images, as well as true centers and regular disks in galaxies classified as highly irregular in rest-frame UV light. Across the 1.5 < z < 2.15 redshift range, regular disks are unveiled in the WFC3 images of ∼25% of both intermediate and high mass galaxies, i.e., above 1010 M☉. Meanwhile, galaxies maintaining diffuse and/or irregular morphologies in the rest-frame optical light–i.e., not yet dynamically settled–at these epochs are almost entirely restricted to masses below 1011 M☉. In contrast at 2.25 < z < 3.5 these diffuse and/or irregular structures overwhelmingly dominate the morphological mix in both the intermediate and high mass regimes, while no regular disks, and only a small fraction (∼25%) of smooth spheroids, are evident above 1011 M☉. Strikingly, by 1.5 < z < 2.25 roughly two out of every three galaxies at the highest masses are spheroids. In our small sample, the fraction of star-forming galaxies at these mass scales decreases concurrently from ∼60% to ∼5%. If confirmed, this indicates that z ∼ 2 is the epoch of both the morphological transformation and quenching of star formation which assemble the first substantial population of massive ellipticals.
galaxies: evolution - galaxies: formation - galaxies: high-redshift
VizieR on-line data:
<Available at CDS (J/ApJ/743/146): erscat.dat udfcat.dat>
[CCO2011] UDFNNNN (Nos 1-1052). [CCO2011] ERSNNNN (Nos 1-3078).
View the references in ADS
To bookmark this query, right click on this link: simbad:2011ApJ...743..146C and select 'bookmark this link' or equivalent in the popup menu