2014MNRAS.443..146J

We present SCUBA-2 (Submillimetre Common-User Bolometer Array) 850µm submillimetre (submm) observations of the fields of 10 dusty, luminous galaxies at z ∼ 1.7-4.6, detected at 12 and/or 22µm by the Wide-field Infrared Survey Explorer (WISE) all-sky survey, but faint or undetected at 3.4 and 4.6µm; dubbed hot, dust-obscured galaxies (Hot DOGs). The six detected targets all have total infrared luminosities greater than 10¹³L_☉, with one greater than 1⁰¹⁴L_☉. Their spectral energy distributions (SEDs) are very blue from mid-infrared to submm wavelengths and not well fitted by standard active galactic nuclei (AGN) SED templates, without adding extra dust extinction to fit the WISE 3.4 and 4.6µm data. The SCUBA-2 850µm observations confirm that the Hot DOGs have less cold and/or more warm dust emission than standard AGN templates, and limit an underlying extended spiral or ULIRG-type galaxy to contribute less than about 2 or 55 percent of the typical total Hot DOG IR luminosity, respectively. The two most distant and luminous targets have similar observed submm to mid-infrared ratios to the rest, and thus appear to have even hotter SEDs. The number of serendipitous submm galaxies detected in the 1.5-arcmin-radius SCUBA-2 850µm maps indicates there is a significant overdensity of serendipitous sources around Hot DOGs. These submm observations confirm that the WISE-selected ultraluminous galaxies have very blue mid-infrared to submm SEDs, suggesting that they contain very powerful AGN, and are apparently located in unusual arcmin-scale overdensities of very luminous dusty galaxies.