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arXiv · astro-ph/0411578

The Phoenix Deep Survey: spectroscopic catalog

J. Afonso·A. Georgakakis·C. Almeida·A. M. Hopkins·L. E. Cram·B. Mobasher·M. Sullivan
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Abstract

The Phoenix Deep Survey is a multi-wavelength survey based on deep 1.4 GHz radio imaging, reaching well into the sub-100 microJy level. One of the aims of this survey is to characterize the sub-mJy radio population, exploring its nature and evolution. In this paper we present the catalog and results of the spectroscopic observations aimed at characterizing the optically ``bright'' (R<~ 21.5 mag) counterparts of faint radio sources. Out of 371 sources with redshift determination, 21% have absorption lines only, 11% show AGN signatures, 32% are star-forming galaxies, 34% show narrow emission lines that do not allow detailed spectral classification (due to poor signal-to-noise ratio and/or lack of diagnostic emission lines) and the remaining 2% are identified with stars. For the star-forming galaxies with a Balmer decrement measurement we find a median extinction of A(Ha)=1.9 mag, higher than that of optically selected samples. This is a result of the radio selection, which is not biased against dusty systems. Using the available spectroscopic information, we estimate the radio luminosity function of star-forming galaxies in two independent redshift bins at z~0.1 and 0.3 respectively. We find direct evidence for strong luminosity evolution of these systems consistent with L(1.4 GHz) ~ (1+z)^(2.7).

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J. Afonso, A. Georgakakis, C. Almeida, A. M. Hopkins, L. E. Cram, B. Mobasher, M. Sullivan. 2005-05-06. The Phoenix Deep Survey: spectroscopic catalog. https://doi.org/10.1086/428923

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