ISO observations of faint radio sources

Deep radio surveys have revealed, below the millijansky level, a population of actively starforming galaxies, undergoing strong luminosity evolution as found from the observed radio source counts. A random sample of 65 sub-mJy radio sources, selected from the Phoenix Deep Survey, was observed at mid and far-infrared wavelengths using the Infrared Space Observatory. Nine sources were detected at both far-infrared and at least one of the mid-infrared wavelengths. A preliminary analysis of the infrared properties of these faint radio sources is carried out by modeling their infrared Spectral Energy Distribution. The radio vs. far-infrared relation, for these faint radio objects, is also presented.