Open AccessA deep Giant Metre‐wave Radio Telescope 610‐MHz survey of the 1 H XMM–Newton / Chandra survey field
Author(s) -
Moss D.,
Seymour N.,
McHardy I. M.,
Dwelly T.,
Page M. J.,
Loaring N. S.
Publication year - 2007
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 - 10.1111/j.1365-2966.2007.11842.x
Subject(s) - physics , astronomy , radio telescope , telescope , astrophysics , metre , field (mathematics) , remote sensing , mathematics , pure mathematics , geology
We present the results of a deep 610‐MHz survey of the 1 H XMM–Newton / Chandra survey area with the Giant Metre‐wave Radio Telescope. The resulting maps have a resolution of ∼7 arcsec and an rms noise limit of 60 μJy. To a 5σ detection limit of 300 μJy, we detect 223 sources within a survey area of 64 arcmin in diameter. We compute the 610‐MHz source counts and compare them to those measured at other radio wavelengths. The well‐known flattening of the Euclidean‐normalized 1.4‐GHz source counts below ∼2 mJy, usually explained by a population of starburst galaxies undergoing luminosity evolution, is seen at 610 MHz. The 610‐MHz source counts can be modelled by the same populations that explain the 1.4‐GHz source counts, assuming a spectral index of −0.7 for the starburst galaxies and the steep spectrum active galactic nucleus (AGN) population. We find a similar dependence of luminosity evolution on redshift for the starburst galaxies at 610 MHz as is found at 1.4 GHz (i.e. ‘ Q ’= 2.45 +0.3 −0.4 ).