The Parkes selected regions: powerful radio galaxies and quasars at high redshifts

A complete sample of extragalactic radio sources with flux density S ≥ 0.1 Jy at 2.7 GHz has been compiled to probe the radio luminosity function to redshifts |z~ 3-4|⁠. VLA maps are presented for the 188 sources in this flux density range; 178 sources remain in the complete sample after examination for confusion. The new radio data define the structures and positions sufficiently well for a re-examination of existing plate material to have yielded an identification content of 56 per cent of the sample down to V ~21. The results from this program will strongly constrain the behaviour of the radio population at high redshifts. Unless the comoving density of sources falls for z > 2, our identification candidates should include many objects with |z~ 3-4|⁠. In fact, the present incomplete data already provide some indications that a redshift cut-off is indeed required for both steep- and flat-spectrum sources.