Identifications of FIRST radio sources in the NOAO Deep-Wide Field Survey

Abstract

In this paper we present the results of an optical and near infrared identification of 514 radio sources from the FIRST survey (Faint Images of the Radio Sky Survey at Twenty centimeters) with a flux-density limit of 1 mJy in the NOAO Deep-Wide Field Survey (NDWFS) Bootes field. Using optical (Bw, R, I) and K band data with approximate limits of Bw ~ 25.5mag, R ~ 25.8 mag, I ~25.5 mag and K~19.4 mag, optical counterparts have been identified for 378 of 514 FIRST radio sources. This corresponds to an identification rate of 34% in four bands (BwRIK), 60% in optical bands (BwRI) and 74% in I band. Photometric redshifts for these sources have been computed using the hyperz code. The inclusion of quasar template spectra in hyperz is investigated. We note that the photometric data are, in many cases, best matched to templates with very short star-formation timescales and the inferred ages of identified galaxies depend strongly on the assumptions about the star-formation timescale. The redshifts obtained are fairly consistent with those expected from the K-z relation for brighter radio sources but there is more scatter in the K-z diagram at z<1.

arXiv comment9 pages, 7 figures. Accepted for publication in Astronomische Nachrichten; will appear in the issue 5/328

References in corpus (37)

• The Sloan Digital Sky Survey: Technical Summary
• The Dust Content and Opacity of Actively Star-Forming Galaxies
• The Demography of Massive Dark Objects in Galaxy Centres
• The many lives of active galactic nuclei: cooling flows, black holes and the luminosities and colours of galaxies
• The 2dF Galaxy Redshift Survey: Spectra and redshifts
• Spectroscopic Target Selection for the Sloan Digital Sky Survey: The Luminous Red Galaxy Sample
• Optical and Radio Properties of Extragalactic Sources Observed by the FIRST and SDSS Surveys
• Near-infrared imaging and the K-z relation for radio galaxies in the 7C Redshift Survey
• Photometric Redshifts in the IRAC Shallow Survey
• Galaxy Formation and Evolution: Low Surface Brightness Galaxies
• Optical and Near-IR Imaging of Ultra Steep Spectrum Radio Sources - The K-z diagram of radio and optically selected galaxies
• A sample of 6C radio sources designed to find objects at redshift > 4: III --- imaging and the radio galaxy K-z relation
• A first sample of faint radio sources with virtually complete redshifts: I. Infrared images, the Hubble diagram, and the alignment effect
• A sample of radio galaxies spanning three decades in radio luminosity - I. The host-galaxy properties and black-hole masses
• The Angular Two-Point Correlation Function for the FIRST Radio Survey
• Deep Westerbork 1.4 GHz Imaging of the Bootes Field
• The LBDS Hercules sample of mJy radio sources at 1.4 GHz - II. Redshift distribution, radio luminosity function, and the high-redshift cut-off
• The 1<z<5 Infrared Luminosity Function of Type I Quasars
• Optical Counterparts for 70,000 Radio Sources: APM Identifications for the FIRST Radio Survey
• Theory and Statistics of Weak Lensing from Large-Scale Mass Inhomogeneities
• The Chandra XBootes Survey - III: Optical and Near-IR Counterparts
• The angular power spectrum of NVSS radio galaxies
• Weak Lensing by Large-Scale Structure with the FIRST Radio Survey
• Optical and X-ray Identification of Faint Radio Sources in the GOODS-S ACS Field
• The 2dF Galaxy Redshift Survey: The population of nearby radio galaxies at the 1 mJy level
• Red Galaxy Clustering in the NOAO Deep Wide-Field Survey
• CENSORS: A Combined EIS-NVSS Survey Of Radio Sources. I. Sample definition, radio data and optical identifications
• The ATESP Radio Survey IV. Optical Identifications and Spectroscopy in the EIS-A Region
• The LBDS Hercules sample of millijansky radio sources at 1.4 GHz: I. Multi-colour photometry
• A Combined EIS-NVSS Survey Of Radio Sources II: Infrared imaging and the K-z relation
• Interpreting the Clustering of Radio Sources
• The TOOT Survey: status and early results
• The clustering of sub-mJy radio sources in The Bootes Deep Field
• The large scale clustering of radio sources
• The Phoenix Deep Survey: Optical and near infrared imaging catalogs
• Optical identifications of $\sim 4000$ radio sources at the 1 mJy level
• The European Large Area ISO Survey (ELAIS): Optical Identifications of 15 micron and 1.4 GHz sources in N1 and N2

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• Probing the Radio Loud/Quiet AGN dichotomy with quasar clustering
• A new search for distant radio galaxies in the Southern hemisphere -- III. Optical spectroscopy and analysis of the MRCR--SUMSS sample
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