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arXiv · 1811.02966

The VLA-COSMOS 3 GHz Large Project: Star formation properties and radio luminosity functions of AGN with moderate-to-high radiative luminosities out to $z\sim6$

Lana Ceraj·Vernesa Smolčić·Ivan Delvecchio·Mladen Novak·Giovanni Zamorani·Jacinta Delhaize·Eva Schinnerer·Eleni Vardoulaki·Noelia Herrera Ruiz
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Abstract

We study a sample of 1,604 moderate-to-high radiative luminosity active galactic nuclei (HLAGN) selected at 3 GHz within the VLA-COSMOS 3 GHz Large Project. These were classified by combining multiple AGN diagnostics: X-ray data, mid-infrared data and broad-band spectral energy distribution fitting. We decompose the total radio 1.4 GHz luminosity ($\mathrm{L_{1.4\ GHz,TOT}}$) into the emission originating from star formation and AGN activity by measuring the excess in $\mathrm{L_{1.4\ GHz,TOT}}$ relative to the infrared-radio correlation of star-forming galaxies. To quantify the excess, for each source we calculate the AGN fraction ($\mathrm{f_{AGN}}$), the fractional contribution of AGN activity to $\mathrm{L_{1.4\ GHz,TOT}}$. The majority of the HLAGN, $(68.0\pm1.5)\%$, are dominated by star-forming processes ($f_{AGN}\leq0.5$), while $(32.0\pm1.5)\%$ are dominated by AGN-related radio emission ($0.5 0$).

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Lana Ceraj, Vernesa Smolčić, Ivan Delvecchio, Mladen Novak, Giovanni Zamorani, Jacinta Delhaize, Eva Schinnerer, Eleni Vardoulaki, Noelia Herrera Ruiz. 2018-11-07. The VLA-COSMOS 3 GHz Large Project: Star formation properties and radio luminosity functions of AGN with moderate-to-high radiative luminosities out to $z\sim6$. https://doi.org/10.1051/0004-6361%2F201833935

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