Observed properties of FRII quasars and radio galaxies at z < 1.0

TL;DR

This study uses high-resolution radio imaging to analyze a complete sample of FRII quasars and radio galaxies at z < 1.0, examining their morphological properties and testing unification models.

Contribution

It provides a systematic analysis of jet, core, lobe, and hotspot properties, supporting unification models with relativistic beaming effects.

Findings

Quasars and broad-line radio galaxies are consistent with being unified with narrow-line objects.

Relativistic beaming influences the properties of kiloparsec-scale jets.

Some properties challenge simple unified models.

Abstract

In a long-term observing project we have imaged a complete sample of FRII quasars and radio galaxies with z < 1.0 at high resolution and high sensitivity with the VLA and MERLIN. This sample of 98 sources includes 15 quasars, 11 broad line radio galaxies and 57 narrow line radio galaxies, allowing unification to be considered in terms of source morphological properties. Radio maps of all the targets have been presented in earlier papers. Here we carry out a systematic analysis of the properties of the jets, cores, lobes and hotspots of objects in the sample. The majority of the tests that we perform show that the data are consistent with a model in which quasars and broad-line radio galaxies are unified with narrow-line objects. Relativistic beaming is the main effect that determines the properties of kiloparsec-scale jets, and it may also have some effect on hotspots. However, some properties of the sample are difficult to account for in simple unified models.