Open AccessQuantifying angular clustering in wide‐area radio surveys
Author(s) -
Blake Chris,
Wall Jasper
Publication year - 2002
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2002.05979.x
Subject(s) - physics , astrophysics , cluster analysis , radio galaxy , galaxy , astronomy , x shaped radio galaxy , correlation function (quantum field theory) , angular resolution (graph drawing) , statistics , mathematics , optoelectronics , combinatorics , dielectric
We quantify the angular clustering of radio galaxies in the NVSS and FIRST surveys using the two‐point correlation function and the moments of counts‐in‐cells – both important points of comparison with theory. These investigations consistently demonstrate that the slope of the correlation function for radio galaxies agrees with that for optically selected galaxies, γ≈ 1.8 . We describe how to disentangle the imprint of galaxy clustering from the two observational problems: resolution of radio galaxies into multiple components and gradients in source surface density induced by difficulties in processing ‘snapshot’ radio observations (significant in both surveys below S 1.4GHz ∼ 15 mJy ). This study disagrees in some respects with previous analyses of the angular clustering of radio galaxies.