Submillimeter Properties of the 1 M[CLC]s[/CLC] Chandra Deep Field–North X-Ray Sample

We present submillimeter observations for 135 of the 370 X-ray sources detected in the 1 Ms exposure of the Chandra Deep Field-North. Nine of the X-ray sources are significantly detected in the submillimeter. The error-weighted mean 850 μm flux is significant at 1.21 ± 0.27 mJy. This value shows little dependence on the 2-8 keV flux from 5 × 10 -16 to 10 -14 ergs cm -2 s -1 , but sources with brighter X-ray fluxes than this appear weak in the submillimeter. The ensemble of X-ray sources contribute about 15% of the extragalactic background light at 850 μm. The submillimeter excess is found to be strongest in the optically faint X-ray sources that are also seen at 20 cm, which is consistent with these X-ray sources being obscured and at high redshift ( z > 1).