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arXiv · astro-ph/0608380

The DEEP2 Galaxy Redshift Survey: AEGIS Observations of a Dual AGN at z=0.7

Brian F. Gerke·Jeffrey A. Newman·Jennifer Lotz·Renbin Yan·P. Barmby·Alison L. Coil·Christopher J. Conselice·R. J. Ivison·Lihwai Lin·David C. Koo·Kirpal Nandra·Samir Salim·Todd Small·Benjamin J. Weiner·Michael C. Cooper·Marc Davis·S. M. Faber·Puragra Guhathakurta
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Abstract

We present evidence for a dual Active Galactic Nucleus (AGN) within an early-type galaxy at z=0.709 in the Extended Groth Strip. The galaxy lies on the red sequence, with absolute magnitude M_B=-21.0 (AB, with h=0.7) and rest-frame color U-B=1.38. Its optical spectrum shows strong, double-peaked [OIII] emission lines and weak Hbeta emission, with Seyfert-like line ratios. The two narrow peaks are separated by 630 km/s in velocity and arise from two distinct regions, spatially resolved in the DEIMOS spectrum, with a projected physical separation of 1.2 kpc. HST/ACS imaging shows an early-type (E/S0) galaxy with hints of disturbed structure, consistent with the remnant of a dissipationless merger. Multiwavelength photometric information from the AEGIS consortium confirms the identification of a dust-obscured AGN in an early-type galaxy, with detections in X-ray, optical, infrared and radio wavebands. These data are most readily explained as a single galaxy harboring two AGN--the first such system to be observed in an otherwise typical early-type galaxy.

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Brian F. Gerke, Jeffrey A. Newman, Jennifer Lotz, Renbin Yan, P. Barmby, Alison L. Coil, Christopher J. Conselice, R. J. Ivison, Lihwai Lin, David C. Koo, Kirpal Nandra, Samir Salim, Todd Small, Benjamin J. Weiner, Michael C. Cooper, Marc Davis, S. M. Faber, Puragra Guhathakurta. 2007-05-02. The DEEP2 Galaxy Redshift Survey: AEGIS Observations of a Dual AGN at z=0.7. https://doi.org/10.1086/517968

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