Abstract

We present SCUBA-2 (Submillimetre Common-User Bolometer Array) 850 mu m submillimetre (submm) observations of the fields of 10 dusty, luminous galaxies at z similar to 1.7-4.6, detected at 12 and/or 22 mu m by the Wide-field Infrared Survey Explorer (WISE) all-sky survey, but faint or undetected at 3.4 and 4.6 mu m; dubbed hot, dust-obscured galaxies (Hot DOGs). The six detected targets all have total infrared luminosities greater than 10(13) L-aS (TM), with one greater than 10(14) L-aS (TM). 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 4.6 mu m data. The SCUBA-2 850 mu m 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 per cent 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-2 850 mu m 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.