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The XMM-Newton/2dF survey - V. the radio properties of the X-ray population

A. Georgakakis·I. Georgantopoulos·I. Leonidaki·Akylas·G. C. Stewart·C. Goudis
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Abstract

In this paper we cross-correlate the FIRST 1.4GHz radio survey with a wide field (~ 1.6deg^2) shallow [f(0.5-8keV) ~ 1e-14erg/s/cm^2] XMM-Newton survey. We find 12 X-ray/radio matches representing 4% of the X-ray selected sample. Most of them are found to be associated with AGNs (total of 9) on the basis of the observed optical spectra (3), radio morphology (2) or X-ray/optical properties (4), while one radio source is identified with an X-ray selected cluster. We also find two sources associated with low redshift galaxies with narrow emission line optical spectra, X-ray luminosity L(0.5-8keV) ~ 1e41erg/s, radio luminosity density L(1.4GHz) ~ 5e22W/Hz and logf_X/f_{opt} ~ -2 suggesting `normal' star-forming galaxies. We argue that radio surveys combined with X-ray sample could provide a powerful tool for identifying X-ray selected `normal' galaxies powered by stellar processes. Finally, radio loud and quiet systems in the present sample have mean X-ray spectral properties consistent with Gamma ~ 1.9.

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A. Georgakakis, I. Georgantopoulos, I. Leonidaki, Akylas, G. C. Stewart, C. Goudis. 2004-05-07. The XMM-Newton/2dF survey - V. the radio properties of the X-ray population. https://doi.org/10.1111/j.1365-2966.2004.07991.x

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