No evidence for a `redshift cut-off' for the most powerful classical double radio sources

Matt J. Jarvis; Steve Rawlings; Chris J. Willott; Katherine M. Blundell; Steve Eales; Mark Lacy

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arXiv · astro-ph/9908106

No evidence for a `redshift cut-off' for the most powerful classical double radio sources

Matt J. Jarvis·Steve Rawlings·Chris J. Willott·Katherine M. Blundell·Steve Eales·Mark Lacy

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Abstract

We use three samples (3CRR, 6CE and 6C*) to investigate the radio luminosity function (RLF) for the `most powerful' low-frequency selected radio sources. We find that the data are well fitted by a model with a constant co-moving space density at high redshift as well as by one with a declining co-moving space density above some particular redshift. This behaviour is very similar to that inferred for steep-spectrum radio quasars by Willott et al (1998) in line with the expectations of Unified Schemes. We conclude that there is as yet no evidence for a `redshift cut-off' in the co-moving space densities of powerful classical double radio sources, and rule out a cut-off at z < 2.5.

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Matt J. Jarvis, Steve Rawlings, Chris J. Willott, Katherine M. Blundell, Steve Eales, Mark Lacy. 1999-08-10. No evidence for a `redshift cut-off' for the most powerful classical double radio sources. https://arxiv.org/abs/astro-ph/9908106

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