The Canada-UK Deep Submillimeter Survey. VII. Optical and Near-Infrared Identifications for the 14 Hour Field

We present the multiwavelength identifications for 23 sources in the Canada-UK Deep Submillimeter Survey (CUDSS) 14h field. The identifications have been selected on the basis of radio and near-infrared data, and we argue that, to our observational limits, both are effective at selecting the correct counterparts of the SCUBA sources. We discuss the properties of these identifications and find that they are very red in near-infrared color, with many classified as extremely red objects, and show disturbed morphologies. Using the entire CUDSS catalog of 50 sources, we use a combination of spectroscopic redshifts (four objects), 1.4 GHz : 850 μm flux ratio redshift estimates (10 objects), and redshift lower limits based on nondetections at 1.4 GHz (the rest of the sample) to estimate a lower limit on the median redshift of the population of zmed > 1.4. Working from simple models and using the properties of the secure identifications, we discuss general and tentative constraints on the redshift distribution and the expected colors and magnitudes of the entire population.