TY - JOUR
T1 - An X-ray-selected active galactic nucleus at z = 4.6 Discovered by the cyder survey
AU - Treister, Ezequiel
AU - Castander, Francisco J.
AU - Maccarone, Thomas J.
AU - Herrera, David
AU - Gawiser, Eric
AU - Maza, José
AU - Coppi, Paolo S.
PY - 2004/3/1
Y1 - 2004/3/1
N2 - We present the discovery of a high-redshift, X-ray-selected active galactic nucleus (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 AGNs. 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 supermassive black hole of ∼108 M⊙ emitting at 1% of its Eddington luminosity. Deep radio observations can discriminate between these two hypotheses.
AB - We present the discovery of a high-redshift, X-ray-selected active galactic nucleus (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 AGNs. 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 supermassive black hole of ∼108 M⊙ emitting at 1% of its Eddington luminosity. Deep radio observations can discriminate between these two hypotheses.
KW - Galaxies: active
KW - Quasars: individual (CXOCY J033716.7-050153)
KW - X-rays: galaxies
UR - http://www.scopus.com/inward/record.url?scp=2142756880&partnerID=8YFLogxK
U2 - 10.1086/381432
DO - 10.1086/381432
M3 - Review article
AN - SCOPUS:2142756880
SN - 0004-637X
VL - 603
SP - 36
EP - 41
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 1 I
ER -