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Radio-quiet objects in the 2QZ survey

M. Wals·B. J. Boyle·S. M. Croom·L. Miller·R. Smith·T. Shanks·P. Outram
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Abstract

Co-addition of blank-field FIRST data at the location of over 8000 QSOs in the 2QZ survey has yielded statistical detections of radio quiet QSOs with median flux levels of 20-40microJy. We show that the total radio flux of radio-quiet QSOs in the 2QZ is consistent with a smooth extrapolation of the 2QZ radio-loud QSO number-flux distribution based on the slope of the relation flattening near the FIRST flux limit. However, we are unable to distinguish a smooth extrapolation of the luminosity function to faint levels from a bimodal luminosity function with a break close to or below the FIRST radio detection limit. We also demonstrate that the redshift dependence of the median radio-to-optical spectral index for these radio quiet QSOs is consistent with that obtained for individual radio-loud 2QZ QSOs detected by FIRST.

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M. Wals, B. J. Boyle, S. M. Croom, L. Miller, R. Smith, T. Shanks, P. Outram. 2005-02-21. Radio-quiet objects in the 2QZ survey. https://doi.org/10.1111/j.1365-2966.2005.08926.x

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