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The DEEP2 Galaxy Redshift Survey: AEGIS observations of a Dual AGNat z = 0.7

Description: 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{sub B} = -21.0 ( AB, w , with h = 0 0.7) and rest-frame color U - B = 1.38. Its optical spectrum shows strong, double-peaked [O III] emission lines and weak H{beta} emission, with Seyfert-like line ratios. The two narrow peaks are separate by 630 km s-1 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 confirm 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.
Date: October 13, 2006
Creator: Gerke1, Brian F.; Newman, Jeffrey A.; Lotz, Jennifer; Yan,Renbin; Barmby, P.; Coil, Alison L. et al.
Partner: UNT Libraries Government Documents Department

Evidence for Merging or Disruption of Red Galaxies from the Evolution of Their Clustering

Description: The formation and evolution of massive red galaxies form a crucial test of theories of galaxy formation based on hierarchical assembly. In this Letter we use observations of the clustering of luminous red galaxies from the Boötes field and N-body simulations to argue that about of the most luminous satellite galaxies appear to undergo merging or disruption within massive halos between and 0.5.
Date: November 29, 2006
Creator: White, Martin; White, Martin; Zheng, Zheng; Brown, Michael J. I.; Dey, Arjun & Jannuzi, Buell T.
Partner: UNT Libraries Government Documents Department

Erratum: "Is there a metallicity-luminosity relationship in active galactic nuclei? The case of narrow-line Seyfert 1 galaxies"

Description: This erratum corrects a computational error affecting the calculation of the intrinsic luminosities of several objects in the article "Is there a metallicity-luminosity relationship in active galactic nuclei? The case of narrow-line Seyfert 1 galaxies." This does not affect any of the main results of the article.
Date: April 10, 2002
Creator: Shemmer, Ohad & Netzer, Hagai
Partner: UNT College of Arts and Sciences

Reddening, Emission-Line, and Intrinsic Absorption Properties in the Narrow-Line Seyfert 1 Galaxy Arakelian 564

Description: This article uses Hubble Space Telescope UV and optical spectra of the narrow-line Seyfert 1 galaxy Ark 564 to investigate its internal reddening and properties of its emission-line and intrinsic UV absorption gas.
Date: October 12, 2001
Creator: Crenshaw, D.M.; Kraemer, S.B.; Turner, T.J.; Collier, S.; Peterson, Bradley M.; Brandt, William Nielsen et al.
Partner: UNT College of Arts and Sciences

Near-Infrared Spectroscopy of High-Redshift Active Galactic Nuclei. II. Disappearing Narrow-Line Regions and the Role of Accretion

Description: This article presents near-infrared spectroscopic measurements of the Hβ region for a sample of 29 luminous high-redshift quasars, and uses the data to discuss the size and other properties of the narrow-line regions in those sources.
Date: June 22, 2004
Creator: Shemmer, Ohad; Netzer, Hagai; Maiolino, Roberto; Oliva, Ernesto; Croom, Scott; Corbett, E. et al.
Partner: UNT College of Arts and Sciences

The deepest X-ray view of high-redshift galaxies: constraints on low-rate black hole accretion

Description: This article exploits the 7 Ms Chandra observations in the Chandra Deep Field-South (CDF-S), the deepest X-ray survey to date, coupled with CANDELS/GOODS-S data, to measure the total X-ray emission arising from 2076 galaxies at 3.5 ≤ z ≤ 6.5.
Date: August 5, 2016
Creator: Vito, F.; Gilli, Roberto; Vignali, Christian; Brandt, William Nielsen; Comastri, Andrea; Yang, G. et al.
Partner: UNT College of Arts and Sciences

The Spectral Energy Distribution and Emission-Line Properties of the Narrow-Line Seyfert 1 Galaxy Arakelian 564

Description: This article presents the intrinsic spectral energy distribution of the narrow-line Seyfert 1 galaxy Ark 564, constructed with contemporaneous data obtained during a multiwavelength, multisatellite observing campaign in 2000 and 2001.
Date: November 7, 2003
Creator: Romano, P.; Mathur, S.; Turner, T.J.; Kraemer, S.B.; Crenshaw, D.M.; Peterson, Bradley M. et al.
Partner: UNT College of Arts and Sciences

FAUST observations of ultraviolet sources in the directions of NGC 4038-39 and 6752

Description: This article discusses an analysis of ultraviolet observations with the FAUST shuttle-borne telescope toward the Antennae and NGC 6752 celestial regions resulting in the detection of 46 and 221 candidate sources respectively, for a signal-to-noise ratio of 8.
Date: December 29, 2000
Creator: Daniels, Julian; Brosch, Noah; Almoznino, Elchanan; Shemmer, Ohad; Bowyer, Stuart & Lampton, Michael
Partner: UNT College of Arts and Sciences

PAH Emission and Star Formation in the Host of the z ~ 2.56 Cloverleaf QSO

Description: This article reports the first detection of the 6.2 and 7.7 μm infrared polycyclic aromatic hydrocarbon emission features in the spectrum of a high-redshift QSO, from the Spitzer IRS spectrum of the Cloverleaf lensed QSO.
Date: March 30, 2007
Creator: Lutz, Dieter; Sturm, Eckhard; Tacconi, Linda; Valiante, Elisabetta; Schweitzer, Mario; Netzer, Hagai et al.
Partner: UNT College of Arts and Sciences

The X-Ray Properties of the Most Luminous Quasars From the Sloan Digital Sky Survey

Description: This article studies the X-ray properties of a representative sample of 59 of the most optically luminous quasars in the universe spanning a redshift range of z ≈ 1.5-4.5.
Date: May 18, 2007
Creator: Just, Dennis W.; Brandt, William Nielsen; Shemmer, Ohad; Steffen, Aaron; Schneider, Donald P.; Chartas, George et al.
Partner: UNT College of Arts and Sciences

Locating Star-Forming Regions in Quasar Host Galaxies

Description: This article presents a study of the morphology and intensity of star formation in the host galaxies of eight Palomar-Green quasars using observations with the Hubble Space Telescope.
Date: November 5, 2013
Creator: Young, Jason E.; Eracleous, Michael; Shemmer, Ohad; Netzer, Hagai; Gronwall, Caryl; Lutz, Dieter et al.
Partner: UNT College of Arts and Sciences

The Evolution of Normal Galaxy X-Ray Emission Through Cosmic History: Constraints from the 6 Ms Chandra Deep Field-South

Description: This article presents measurements of the evolution of normal-galaxy X-ray emission from z ≈ 0-7 using local galaxies and galaxy samples in the ≈6 Ms Chandra Deep Field-South (CDF-S) survey.
Date: June 24, 2016
Creator: Lehmer, Bret; Basu-Zych, A.; Mineo, S.; Brandt, William Nielsen; Eufrasio, R. T.; Fragos, T. et al.
Partner: UNT College of Arts and Sciences

Black Hole Growth Is Mainly Linked to Host-galaxy Stellar Mass Rather Than Star Formation Rate

Description: This article investigates the dependence of black hole accretion rate (BHAR) on host-galaxy star formation rate (SFR) and stellar mass in the CANDELS/GOODS-South field in the redshift range of 0.5 ⩽ z < 2.0.
Date: June 15, 2017
Creator: Yang, G.; Chen, C. -T. J.; Vito, F.; Brandt, William Nielsen; Alexander, David M.; Luo, Bin et al.
Partner: UNT College of Arts and Sciences

Weak Line Quasars at High Redshift: Extremely High Accretion Rates or Anemic Broad-Line Regions?

Description: This article presents Gemini-North K-band spectra of two representative members of the class of high-redshift quasars with exceptionally weak rest-frame ultraviolet emission lines.
Date: September 8, 2010
Creator: Shemmer, Ohad; Trakhtenbrot, Benny; Anderson, Scott F.; Brandt, William Nielsen; Diamond-Stanic, Aleksandar M.; Fan, Xiaohui et al.
Partner: UNT College of Arts and Sciences

A Population of X-Ray Weak Quasars: PHL 1811 Analogs at High Redshift

Description: This article reports the results from Chandra and XMM-Newton observations of a sample of 10 type 1 quasars selected to have unusual UV emission-line properties similar to those of PHL 1811.
Date: April 15, 2011
Creator: Wu, Jianfeng; Brandt, William Nielsen; Hall, Patrick B.; Gibson, Robert R.; Richards, Gordon T.; Schneider, Donald P. et al.
Partner: UNT College of Arts and Sciences