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An X-ray Selected AGN at z=4.6 Discovered by the CYDER Survey

Ezequiel Treister·Francisco J. Castander·Thomas J. Maccarone·David Herrera·Eric Gawiser·Jose Maza·Paolo S. Coppi
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Abstract

We present the discovery of a high redshift, X-ray selected AGN by the Calan-Yale Deep Extragalactic Research (CYDER) survey: CXOCY J033716.7-050153, located at $z=4.61$, the second high redshift AGN discovered by this survey. Here, we present its optical, near-IR and X-ray properties and compare it with other optical and X-ray selected high redshift AGN. The optical luminosity of this object is significantly lower than most optically selected high redshift quasars. It also has a lower rest frame UV to X-ray emission ratio than most known quasars at this redshift. This mild deviation can be explained either by dust obscuring the UV radiation of a normal radio quiet AGN emitting at 10% of its Eddington luminosity or because this is intrinsically a low luminosity radio loud AGN, with a super-massive Black Hole of $\sim 10^8M_\sun$ emitting at 1% of its Eddington luminosity. Deep radio observations can discriminate between these two hypotheses.

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Ezequiel Treister, Francisco J. Castander, Thomas J. Maccarone, David Herrera, Eric Gawiser, Jose Maza, Paolo S. Coppi. 2003-11-15. An X-ray Selected AGN at z=4.6 Discovered by the CYDER Survey. https://doi.org/10.1086/381432

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