Far-IR Emission From Dust-Obscured Galaxies
  Dust-obscured galaxies (DOGs) are a UV-faint, IR-bright galaxy population
that reside at z~2 and are believed to be in a phase of dusty star-forming and
AGN activity. We present far-IR observations of a complete sample of DOGs in
the 2 deg2 of COSMOS. The 3077 DOGs have <z>=1.9+/-0.3 and are selected from
24um and r+ observations using a color cut of r+ - [24]>=7.5 (AB mag) and
S24>=100uJy. Based on the near-IR SEDs, 47% are star-formation dominated and
10% are AGN-dominated. We use SPIRE far-IR photometry from HerMES to calculate
the IR luminosity and characteristic dust temperature for the 1572 (51%) DOGs
that are detected at 250um (>=3{\sigma}). For the remaining 1505 (49%) that are
undetected, we perform a median stacking analysis to probe fainter
luminosities. Detected and undetected DOGs have average IR luminosities of
(2.8+/-0.4) x 1012 LSun and (0.77+-0.08)x10^12LSun, and dust temperatures of
34+/-7 K and 37+/-3 K, respectively. The IR luminosity function of DOGs with
S24>=100uJy is calculated, using far-IR observations and stacking. DOGs
contribute 10-30% to the total star formation rate density of the Universe at
z=1.5-2.5, dominated by 250um detected and bump DOGs. For comparison, DOGs
contribute 30% to the star-formation rate density of the Universe for all
galaxies at z=1.5-2.5 with S24>=100uJy. DOGs have a large scatter about the
star-formation main sequence and their specific star-formation rates show that
the observed phase of star-formation could be responsible for their observed
stellar mass at z~2.
