2007MNRAS.381.1093H

We present deep, multi-Very Large Array configuration radio images for a set of 18 quasars, having redshifts between 0.36 and 2.5, from the 7C quasar survey. Approximately one quarter of these quasars have Fanaroff-Riley type I (FRI) type twin-jet structures and the remainder are a broad range of wide angle tail, fat double, classical double, core-jet and hybrid sources. These images demonstrate that FRI quasars are prevalent in the Universe, rather than non-existent as had been suggested in the literature prior to the serendipitous discovery of the first FRI quasar a few years ago, the optically powerful `radio-quiet' quasar E1821+643.

Some of the FRI quasars have radio luminosities exceeding the traditional FRI/FRII break luminosity; however, we find no evidence for FRII quasars with luminosities significantly below the break. We consider whether the existence of such high-luminosity FRI structures is due to the increasingly inhomogeneous environments in the higher redshift Universe.