We use deep far-IR , submm , radio and X-ray imaging and mid-IR spectroscopy to explore the nature of a sample of Spitzer -selected dust-obscured galaxies ( DOGs ) in GOODS-N. A sample of 79 galaxies satisfy the criteria R - [ 24 ] > 14 ( Vega ) down to S _ { 24 } > 100 \mu Jy ( median flux density S _ { 24 } = 180 \mu Jy ) .
Twelve of these galaxies have IRS spectra available which we use to measure redshifts and classify these objects as being dominated by star formation or active galactic nuclei ( AGN ) activity in the mid-IR .
The IRS spectra and Spitzer photometric redshifts confirm that the DOGs lie in a tight redshift distribution around z \sim 2 .
Based on mid-IR colors , 80 % of DOGs are likely dominated by star formation ; the stacked X-ray emission from this sub-sample of DOGs is also consistent with star formation .
Since only a small number of DOGs are individually detected at far-IR and submm wavelengths , we use a stacking analysis to determine the average flux from these objects and plot a composite IR ( 8–1000 \mu m ) spectral energy distribution ( SED ) .
The average luminosity of these star forming DOGs is L _ { IR } \sim 1 \times 10 ^ { 12 } L _ { \odot } .
We compare the average star forming DOG to the average bright ( S _ { 850 } > 5 mJy ) submillimeter galaxy ( SMG ) ; the S _ { 24 } > 100 \mu Jy DOGs are 3 times more numerous but 8 times less luminous in the IR .
The far-IR SED shape of DOGs is similar to that of SMGs ( average dust temperature of around 30 K ) but DOGs have a higher mid-IR to far-IR flux ratio .
The average star formation-dominated DOG has a star formation rate of 200 { M _ { \odot } yr ^ { -1 } } which , given their space density , amounts to a contribution of 0.01 { M _ { \odot } yr ^ { -1 } Mpc ^ { -3 } } ( or 5–10 % ) to the star formation rate density at z \sim 2 .
We use the composite SED to predict the average flux of DOGs in future Herschel /PACS 100 \mu m and SCUBA-2 450 \mu m surveys and show that the majority of them will be detected .