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  Partner: UNT College of Arts and Sciences
 Collection: UNT Scholarly Works
Optically Selected BL Lacertae Candidates from the Sloan Digital Sky Survey Data Release Seven

Optically Selected BL Lacertae Candidates from the Sloan Digital Sky Survey Data Release Seven

Date: October 30, 2009
Creator: Plotkin, Richard M.; Anderson, Scott F.; Brandt, William Nielsen; Diamond-Stanic, Aleksandar M.; Fan, Xiaohui; Hall, Patrick B. et al.
Description: This article presents a sample of 723 optically selected BL Lac candidates from the Sloan Digital Sky Survey Data Release 7 spectroscopic database.
Contributing Partner: UNT College of Arts and Sciences
A Population of X-Ray Weak Quasars: PHL 1811 Analogs at High Redshift

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

Date: April 15, 2011
Creator: Wu, Jianfeng; Brandt, William Nielsen; Hall, Patrick B.; Gibson, Robert R.; Richards, Gordon T.; Schneider, Donald P. et al.
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.
Contributing Partner: UNT College of Arts and Sciences
Variability-Selected Low-Luminosity Active Galactic Nuclei in the 4 Ms Chandra Deep Field-South

Variability-Selected Low-Luminosity Active Galactic Nuclei in the 4 Ms Chandra Deep Field-South

Date: January 18, 2012
Creator: Young, Monica; Brandt, William Nielsen; Xue, Yongquan; Alexander, David M.; Bauer, Franz E.; Lehmer, Bret et al.
Description: This article demonstrates that the observed variability cannot be explained by X-ray Binary populations or ultraluminous X-ray sources, so the variability is most likely caused by accretion onto a supermassive black hole.
Contributing Partner: UNT College of Arts and Sciences
On The Performance of Quasar Reverberation Mapping in the Era of Time-Domain Photometric Surveys

On The Performance of Quasar Reverberation Mapping in the Era of Time-Domain Photometric Surveys

Date: February 2, 2014
Creator: Chelouche, Doron; Shemmer, Ohad; Cotlier, Gabriel I.; Barth, Aaron J. & Rafter, Stephen E.
Description: This article quantitatively assesses, by means of comprehensive numerical simulations, the ability of broadband photometric surveys to recover the broad emission line region size in quasars under various observing conditions and for a wide range of object properties.
Contributing Partner: UNT College of Arts and Sciences
Star Formation in the Hosts of High-z QSOs: Evidence from Spitzer PAH Detections

Star Formation in the Hosts of High-z QSOs: Evidence from Spitzer PAH Detections

Date: May 17, 2008
Creator: Lutz, Dieter; Sturm, Eckhard; Tacconi, Linda; Valiante, Elisabetta; Schweitzer, Mario; Netzer, Hagai et al.
Description: This article presents Spitzer rest frame mid-infrared spectroscopy of 12z~2 millimeter-bright type 1 QSOs.
Contributing Partner: UNT College of Arts and Sciences
PAH Emission and Star Formation in the Host of the z ~ 2.56 Cloverleaf QSO

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

Date: March 30, 2007
Creator: Lutz, Dieter; Sturm, Eckhard; Tacconi, Linda; Valiante, Elisabetta; Schweitzer, Mario; Netzer, Hagai et al.
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.
Contributing Partner: UNT College of Arts and Sciences
The X-Ray Properties of the Most Luminous Quasars From the Sloan Digital Sky Survey

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

Date: May 18, 2007
Creator: Just, Dennis W.; Brandt, William Nielsen; Shemmer, Ohad; Steffen, Aaron; Schneider, Donald P.; Chartas, George et al.
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.
Contributing Partner: UNT College of Arts and Sciences
X-Ray Spectral Constraints for z ≈ 2 Massive Galaxies: The Identification of Reflection-Dominated Active Galactic Nuclei

X-Ray Spectral Constraints for z ≈ 2 Massive Galaxies: The Identification of Reflection-Dominated Active Galactic Nuclei

Date: June 6, 2011
Creator: Alexander, David M.; Bauer, Franz E.; Brandt, William Nielsen; Daddi, Emanuele; Hickox, Ryan; Lehmer, Bret et al.
Description: This article uses the 4 Ms Chandra Deep Field-South survey to place direct constraints on the ubiquity of z ≈ 2 heavily obscured active galactic nuclei.
Contributing Partner: UNT College of Arts and Sciences
Locating Star-Forming Regions in Quasar Host Galaxies

Locating Star-Forming Regions in Quasar Host Galaxies

Date: November 5, 2013
Creator: Young, Jason E.; Eracleous, Michael; Shemmer, Ohad; Netzer, Hagai; Gronwall, Caryl; Lutz, Dieter et al.
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.
Contributing Partner: UNT College of Arts and Sciences
A Statistical Relation Between the X-ray Spectral Index and Eddington Ratio of Active Galactic Nuclei in Deep Surveys

A Statistical Relation Between the X-ray Spectral Index and Eddington Ratio of Active Galactic Nuclei in Deep Surveys

Date: May 22, 2013
Creator: Brightman, M.; Silverman, John David; Mainieri, Vincenzo; Ueda, Yoshihiro; Schramm, Malte; Matsuoka, Kenta et al.
Description: This article presents an investigation into how well the properties of the accretion flow on to a supermassive black hole may be coupled to those of the overlying hot corona.
Contributing Partner: UNT College of Arts and Sciences
The Chandra Deep Field-South Survey: 2 Ms Source Catalogs

The Chandra Deep Field-South Survey: 2 Ms Source Catalogs

Date: April 21, 2008
Creator: Luo, Bin; Bauer, Franz E.; Brandt, William Nielsen; Alexander, David M.; Lehmer, Bret; Schneider, Donald P. et al.
Description: This article presents point-source catalogs for the ≈2 Ms exposure of the Chandra Deep Field-South.
Contributing Partner: UNT College of Arts and Sciences
Black Hole Mass and Growth Rate at High Redshift

Black Hole Mass and Growth Rate at High Redshift

Date: August 27, 2007
Creator: Netzer, Hagai; Lira, Paulina; Trakhtenbrot, Benny; Shemmer, Ohad & Cury, Iara
Description: This article presents new H- and K-band spectroscopy of 15 high-luminosity active galactic nuclei at redshifts 2.3-3.4 obtained with Gemini South.
Contributing Partner: UNT College of Arts and Sciences
Exploratory X-Ray Monitoring of Luminous Radio-Quiet Quasars at High Redshift: Initial Results

Exploratory X-Ray Monitoring of Luminous Radio-Quiet Quasars at High Redshift: Initial Results

Date: January 17, 2014
Creator: Shemmer, Ohad; Brandt, William Nielsen; Paolillo, Maurizio; Kaspi, Shai; Vignali, Christian; Stein, Matthew S. et al.
Description: This article presents initial results from an exploratory X-ray monitoring project of two groups of comparably luminous radio-quiet quasars.
Contributing Partner: UNT College of Arts and Sciences
Dust Covering Factor, Silicate Emission, and Star Formation in Luminous QSOs

Dust Covering Factor, Silicate Emission, and Star Formation in Luminous QSOs

Date: April 5, 2007
Creator: Maiolino, Roberto; Shemmer, Ohad; Imanishi, Masatoshi; Netzer, Hagai; Oliva, Ernesto; Lutz, Dieter et al.
Description: This article presents Spitzer IRS low resolution, mid-IR spectra of a sample of 25 high luminosity QSOs at 2 < z < 3.5.
Contributing Partner: UNT College of Arts and Sciences
GRB 060505: A Possible Short-Duration Gamma-Ray Burst in a Star-Forming Region at a Redshift of 0.09

GRB 060505: A Possible Short-Duration Gamma-Ray Burst in a Star-Forming Region at a Redshift of 0.09

Date: March 13, 2007
Creator: Ofek, Efran; Cenko, Brad; Gal-Yam, Avishay; Fox, Derek B.; Nakar, Ehud; Rau, Arne et al.
Description: This article reports the discovery of the GRB optical afterglow and observations of its environment using Gemini South, the Hubble Space Telescope, Chandra, Swift, and the Very Large Array.
Contributing Partner: UNT College of Arts and Sciences
The Hard X-Ray Spectrum as a Probe for Black Hole Growth in Radio-Quiet Active Galactic Nuclei

The Hard X-Ray Spectrum as a Probe for Black Hole Growth in Radio-Quiet Active Galactic Nuclei

Date: April 3, 2008
Creator: Shemmer, Ohad; Brandt, William Nielsen; Netzer, Hagai; Maiolino, Roberto & Kaspi, Shai
Description: This article studies the hard X-ray spectral properties of 10 highly luminous radio-quiet active galactic nuclei at z = 1.3-3.2, including new XMM-Newton observations of four of these sources.
Contributing Partner: UNT College of Arts and Sciences
A Comprehensive Analysis of Groundwater Quality in the Barnett Shale Region

A Comprehensive Analysis of Groundwater Quality in the Barnett Shale Region

Date: June 16, 2015
Creator: Hildenbrand, Zacariah Louis; Carlton Jr., Doug D.; Fontenot, Brian; Meik, Jesse M.; Walton, Jayme; Taylor, Josh et al.
Description: This article presents an analysis of 550 groundwater samples collected from private and public supply water wells drawing from aquifers overlying the Barnett shale formation of Texas.
Contributing Partner: UNT College of Arts and Sciences
Weak Line Quasars at High Redshift: Extremely High Accretion Rates or Anemic Broad-Line Regions?

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

Date: September 8, 2010
Creator: Shemmer, Ohad; Trakhtenbrot, Benny; Anderson, Scott F.; Brandt, William Nielsen; Diamond-Stanic, Aleksandar M.; Fan, Xiaohui et al.
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.
Contributing Partner: UNT College of Arts and Sciences
Star Formation and Black Hole Growth at z ≃4.8

Star Formation and Black Hole Growth at z ≃4.8

Date: May 29, 2014
Creator: Netzer, Hagai; Mor, Rivay; Trakhtenbrot, Benny; Shemmer, Ohad & Lira, Paulina
Description: This article reports Herschel/SPIRE, Spitzer and Wide-field Infrared Survey Explorer obervations of 44 z ≃ 4.8 optically selected active galactic nuclei.
Contributing Partner: UNT College of Arts and Sciences
The Ultraviolet-To-Mid-Infrared Spectral Energy Distribution of Weak Emission Line Quasars

The Ultraviolet-To-Mid-Infrared Spectral Energy Distribution of Weak Emission Line Quasars

Date: September 23, 2011
Creator: Lane, Ryan A.; Shemmer, Ohad; Diamond-Stanic, Aleksandar M.; Fan, Xiaohui; Anderson, Scott F.; Brandt, William Nielsen et al.
Description: This article presents Spitzer Space Telescope photometry of 18 Sloan Digital Sky Survey quasars which have weak or undetectable high-ionization emission lines in their rest-frame ultraviolet spectra.
Contributing Partner: UNT College of Arts and Sciences
X-Ray and Multiwavelength Insights into the Nature of Weak Emission-Line Quasars at Low Redshift

X-Ray and Multiwavelength Insights into the Nature of Weak Emission-Line Quasars at Low Redshift

Date: December 9, 2011
Creator: Wu, Jianfeng; Brandt, William Nielsen; Anderson, Scott F.; Diamond-Stanic, Aleksandar M.; Hall, Patrick B.; Plotkin, Richard M. et al.
Description: This article reports on the X-ray and multiwavelength properties of 11 radio-quiet quasars with weak or no emission lines identified by the Sloan Digital Sky Survey with redshift.
Contributing Partner: UNT College of Arts and Sciences
The X-Ray Properties of the Optically Brightest Mini-Bal Quasars from the Sloan Digital Sky Survey

The X-Ray Properties of the Optically Brightest Mini-Bal Quasars from the Sloan Digital Sky Survey

Date: September 12, 2010
Creator: Wu, Jianfeng; Brandt, William Nielsen; Comins, M.L.; Gibson, Robert R.; Shemmer, Ohad; Garmire, Gordon P. et al.
Description: This article compiles a sample of 14 of the optically brightest radio-quiet quasars in the Sloan Digital Sky Survey Data Release 5 quasar catalog that have mini-broad absorption lines present in their spectra.
Contributing Partner: UNT College of Arts and Sciences
X-Ray Insights Into the Nature of Weak Emission-Line Quasars at High Redshift

X-Ray Insights Into the Nature of Weak Emission-Line Quasars at High Redshift

Date: February 8, 2009
Creator: Shemmer, Ohad; Brandt, William Nielsen; Anderson, Scott F.; Diamond-Stanic, Aleksandar M.; Fan, Xiaohui; Richards, Gordon T. et al.
Description: This article presents Chandra observations of nine high-redshift quasars discovered by the Sloan Digital Sky Survey with weak or undetectable high-ionization emission lines in their UV spectra.
Contributing Partner: UNT College of Arts and Sciences
The X-Ray Properties of Typical High-Redshift Radio-Loud Quasars

The X-Ray Properties of Typical High-Redshift Radio-Loud Quasars

Date: June 12, 2011
Creator: Saez, Christian; Brandt, William Nielsen; Shemmer, Ohad; Chomiuk, Laura; Lopez, Laura A.; Marshall, Herman L. et al.
Description: This article reports spectral, imaging, and variability results from four XMM-Newton observations and two Chandra observations of high-redshift radio-loud quasars.
Contributing Partner: UNT College of Arts and Sciences