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arXiv · 1712.09838

Cosmic evolution of AGN with moderate-to-high radiative luminosity in the COSMOS field

Lana Ceraj·Vernesa Smolčić·Ivan Delvecchio·Jacinta Delhaize·Mladen Novak
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Abstract

We study the moderate-to-high radiative luminosity active galactic nuclei (HLAGN) within the VLA-COSMOS 3 GHz Large Project. The survey covers 2.6 square degrees centered on the COSMOS field with a 1$σ$ sensitivity of 2.3 $\mathrm{μJy}$/beam across the field. This provides the simultaneously largest and deepest radio continuum survey available to date with exquisite multi-wavelength coverage. The survey yields 10,830 radio sources with signal-to-noise ratios $\geq$5. A subsample of 1,604 HLAGN is analyzed here. These were selected via a combination of X-ray luminosity and mid-infrared colors. We derive luminosity functions for these AGN and constrain their cosmic evolution out to a redshift of $z\sim6$, for the first time decomposing the star formation and AGN contributions to the radio continuum emission in the AGN. We study the evolution of number density and luminosity density finding a peak at $z\sim1.5$ followed by a decrease out to a redshift $z\sim6$.

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Lana Ceraj, Vernesa Smolčić, Ivan Delvecchio, Jacinta Delhaize, Mladen Novak. 2017-12-28. Cosmic evolution of AGN with moderate-to-high radiative luminosity in the COSMOS field. https://doi.org/10.1017/s1743921318000030

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