Bibcode
Calanog, J. A.; Wardlow, J.; Fu, Hai; Cooray, A.; Assef, R. J.; Bock, J.; Casey, C. M.; Conley, A.; Farrah, D.; Ibar, E.; Kartaltepe, J.; Magdis, G.; Marchetti, L.; Oliver, S. J.; Pérez-Fournon, I.; Riechers, D.; Rigopoulou, D.; Roseboom, I. G.; Schulz, B.; Scott, Douglas; Symeonidis, M.; Vaccari, M.; Viero, M.; Zemcov, M.
Bibliographical reference
The Astrophysical Journal, Volume 775, Issue 1, article id. 61, 10 pp. (2013).
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9
2013
Journal
Citations
18
Refereed citations
17
Description
Dust-obscured galaxies (DOGs) are an ultraviolet-faint, infrared-bright
galaxy population that reside at z ~ 2 and are believed to be in a phase
of dusty star-forming and active galactic nucleus (AGN) activity. We
present far-infrared (far-IR) observations of a complete sample of DOGs
in the 2 deg2 of the Cosmic Evolution Survey. The 3077 DOGs
have langzrang = 1.9 ± 0.3 and are selected from 24 μm and r
+ observations using a color cut of r + –
[24] >= 7.5 (AB mag) and S 24 >= 100 μJy. Based on
the near-IR spectral energy distributions, 47% are bump DOGs (star
formation dominated) and 10% are power-law DOGs (AGN-dominated). We use
SPIRE far-IR photometry from the Herschel Multi-tiered Extragalactic
Survey to calculate the IR luminosity and characteristic dust
temperature for the 1572 (51%) DOGs that are detected at 250 μm
(>=3σ). For the remaining 1505 (49%) that are undetected, we
perform a median stacking analysis to probe fainter luminosities.
Herschel-detected and undetected DOGs have average luminosities of (2.8
± 0.4) × 1012 L ⊙ and (0.77
± 0.08) × 1012 L ⊙, and dust
temperatures of (33 ± 7) K and (37 ± 5) K, respectively.
The IR luminosity function for DOGs with S 24 >= 100
μJy is calculated, using far-IR observations and stacking. DOGs
contribute 10%-30% to the total star formation rate (SFR) density of the
universe at z = 1.5-2.5, dominated by 250 μm detected and bump DOGs.
For comparison, DOGs contribute 30% to the SFR density for all z =
1.5-2.5 galaxies with S 24 >= 100 μJy. DOGs have a
large scatter about the star formation main sequence and their specific
SFRs show that the observed phase of star formation could be responsible
for their total observed stellar mass at z ~ 2.
Related projects
Formation and Evolution of Galaxies: Observations in Infrared and other Wavelengths
This IAC research group carries out several extragalactic projects in different spectral ranges, using space as well as ground-based telescopes, to study the cosmological evolution of galaxies and the origin of nuclear activity in active galaxies. The group is a member of the international consortium which built the SPIRE instrument for the
Ismael
Pérez Fournon