2000A&A...360...92B

We present millimeter wavelength detections of three faint sources that are most likely high-redshift starburst galaxies. For one of the sources, which was previously discovered with SCUBA at 850µm, we present a detection with the IRAM interferometer at 240GHz (1.25mm) that shows the object unresolved at an angular resolution of 2.5", and coincident within 1'' with a radio source and a galaxy detected in the near-infrared. The two other sources were discovered in a deep 250GHz (1.2mm) survey with the Max-Planck Millimeter Bolometer (MAMBO) array at the IRAM 30 m telescope. Both have fluxes of ≃4mJy and radio counterparts with a 1.4GHz flux density of ≃75µJy. Their radio-to-mm flux ratios suggest redshifts larger than 2. Both sources are faint in the optical and near-infrared, one showing a 20.5mag K-band counterpart. From our data and that available in the literature, we estimate the redshift distribution of twenty-two faint mm and sub-mm sources and conclude that the majority of them are likely to be at z >2.