Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: No evidence for a `redshift cut-off' for the most powerful classical
  double radio sources   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.

17
The categories of this paper are: q-fin
7
The categories of this paper are: hep-th
0
The categories of this paper are: hep-ph
34
The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
2
The categories of this paper are: math
9
The categories of this paper are: nlin
4
The categories of this paper are: cond-mat
13
The categories of this paper are: quant-ph
8
The categories of this paper are: hep-ex
3
The categories of this paper are: physics
21
The categories of this paper are: adap-org
20
The categories of this paper are: acc-phys
22
The categories of this paper are: chao-dyn
32
The categories of this paper are: atom-ph