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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.
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Partner: UNT College of Science
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High-redshift AGN in the Chandra Deep Fields: the obscured fraction and space density of the sub-L∗ population

Description: This article investigates the population of high-redshift (3≤z<6) active galactic nuclei (AGN) selected in the two deepest X-ray surveys, the 7 Ms Chandra Deep Field-South and 2 Ms Chandra Deep Field-North.
Date: September 26, 2017
Creator: Vito, F.; Brandt, William Nielsen; Yang, G.; Gilli, Roberto; Luo, Bin; Vignali, Christian et al.
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Partner: UNT College of Science
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Tracing the accretion history of supermassive black holes through X-ray variability: results from the Chandra Deep Field-South

Description: This article studies the X-ray variability properties of distant active galactic nuclei (AGNs) in the Chandra Deep Field-South region over 17 yr, up to z ~ 4, and compare them with those predicted by models based on local samples.
Date: July 14, 2017
Creator: Paolillo, Maurizio; Papadakis, I.; Brandt, William Nielsen; Luo, Bin; Xue, Yongquan; Tozzi, Paolo et al.
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Partner: UNT College of Science
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Placing High-Redshift Quasars in Perspective: Unifying Distant Quasars with Their Lower Redshift Counterparts through Near-Infrared Spectroscopy

Description: I present spectroscopic measurements for 260 sources from the Gemini Near Infrared Spectrograph–Distant Quasar Survey (GNIRS-DQS). Being the largest uniform, homogeneous survey of its kind, it represents a flux-limited sample of Sloan Digital Sky Survey (SDSS) quasars at 1.5 < z < 3.5. A combination of the GNIRS and SDSS spectra covers principal quasar diagnostic features, chiefly the C IV λ1549, Mg II λλ2798, 2803, Hβ λ4861, and [O III] λλ4959, 5007 emission lines, in each source. The spectral… more
Date: May 2023
Creator: Matthews, Brandon M.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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ALMA Observations of Quasar Host Galaxies at z ≃ 4.8

Description: Article presents ALMA Band 7 data of the [C ıı] 𝜆157.74 𝜇m emission line and underlying far-IR (FIR) continuum for 12 luminous quasars at 𝓏 ≃ 4.8 powered by fast-growing supermassive black holes (SMBHs).
Date: May 27, 2020
Creator: Shemmer, Ohad; Nguyen, Nathen H.; Lira, Paulina; Trakhtenbrot, Benny; Netzer, Hagai; Cicone, Claudia et al.
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Partner: UNT College of Science
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Ionised outflows in z ~ 2.4 quasar host galaxies

Description: This article presents a kinematical analysis of the [OIII]λ5007 emission line observed in six high-luminosity quasars at z ~ 2.4.
Date: August 1, 2015
Creator: Carniani, Stefano; Marconi, Alessandro; Maiolino, Roberto; Balmaverde, Barbara; Brusa, Marcella; Cano-Díaz, Mariana et al.
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Partner: UNT College of Arts and Sciences

Chandra and Magellan/FIRE follow-up observations of PSO167–13: An X-ray weak QSO at z = 6.515

Description: This article presents the results of follow-up observations of the z = 6.515 radio-quiet QSO PSO167–13, which is interacting with a close companion galaxy with the goal to confirm the existence of the X-ray source and to investigate the rest-frame UV properties of the QSO. The authors observed the PSO167–13 system with Chandra/ACIS-S (177 ks) and obtained new spectroscopic observations (7.2 h) with Magellan/FIRE.
Date: May 27, 2021
Creator: Vito, F.; Brandt, William Nielsen; Ricci, F.; Congui, E.; Connor, T.; Bañados, E. et al.
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Partner: UNT College of Science
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Shedding New Light on Weak Emission-Line Quasars in the CIV-Hβ Parameter Space

Description: Article describes how weak emission-line quasars (WLQs) are a subset of Type 1 quasars that exhibit extremely weak Lyα+N V λ1240 and/or C IV λ1549 emission lines. The authors investigate the relationship between emission-line properties and accretion rate for a sample of 230 `ordinary' Type 1 quasars and 18 WLQs at z<0.5 and 1.5<z<3.5 that have rest-frame ultraviolet and optical spectral measurements.
Date: April 10, 2023
Creator: Ha, Trung; Dix, Cooper; Matthews, Brandon M.; Shemmer, Ohad; Brotherton, Michael S.; Myers, Adam D. et al.
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Partner: UNT College of Science
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A new, faint population of X-ray transients

Description: This article reports on the detection of a remarkable new fast high-energy transient found in the Chandra Deep Field-South, robustly associated with a faint host in the CANDELS survey.
Date: February 15, 2017
Creator: Bauer, Franz E.; Treister, Ezequiel; Schawinski, K.; Schulze, S.; Luo, Bin; Alexander, David M. et al.
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Partner: UNT College of Arts and Sciences
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ALMA Observations Show Major Mergers Among the Host Galaxies of Fast-growing, High-redshift, Supermassive Black Holes

Description: This article presents new ALMA band-7 data for a sample of six luminous quasars at z ≃ 4.8, powered by fast-growing supermassive black holes (SMBHs) with rather uniform properties.
Date: February 3, 2017
Creator: Trakhtenbrot, Benny; Lira, Paulina; Netzer, Hagai; Cicone, Claudia; Maiolino, Roberto & Shemmer, Ohad
Item Type: Refine your search to only Article
Partner: UNT College of Arts and Sciences
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Long-Term X-Ray Variability of Typical Active Galactic Nuclei in the Distant Universe

Description: This article discusses the long-term (≈15 years, observed frame) X-ray variability analyses of the 68 brightest radio-quiet active galactic nuclei (AGNs) in the 6 Ms Chandra Deep Field-South survey.
Date: November 3, 2016
Creator: Yang, G.; Brandt, William Nielsen; Luo, Bin; Xue, Yongquan; Bauer, Franz E.; Sun, M. et al.
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Partner: UNT College of Arts and Sciences
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An Extreme X-Ray Variability Event of a Weak-line Quasar

Description: Article reports the discovery of an extreme X-ray flux rise (by a factor of ≳20) of the weak-line quasar Sloan Digital Sky Survey (SDSS) J153913.47+395423.4 (hereafter SDSS J1539+3954) at z = 1.935. SDSS J1539+3954 is the most-luminous object among radio-quiet type 1 active galactic nuclei (AGNs) where such dramatic X-ray variability has been observed.
Date: February 3, 2020
Creator: Ni, Q.; Brandt, W. N.; Yi, W.; Luo, B.; Timlin, J. D., III; Hall, P. B. et al.
Item Type: Refine your search to only Article
Partner: UNT College of Science
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The universal shape of the X-ray variability power spectrum of AGN up to z ∼ 3

Description: Authors of the article assert that they studied the ensemble X-ray variability properties of active galactic nuclei (AGN) over large ranges of timescale (20 ks ≤ T ≤ 14 yr), redshift (0 ≤ z ≲ 3), luminosity (1040 erg s−1 ≤ LX ≤ 1046 erg s−1), and black hole (BH) mass (106 ≤ M⊙ ≤ 109). The authors show that the data collected from archival observations and previous literature studies are fully consistent with a universal PSD form, which does not show any evidence for systematic evolution of shap… more
Date: May 8, 2023
Creator: Paolillo, Maurizio; Papadakis, I.; Brandt, William Nielsen; Bauer, Franz E.; Lanzuisi, G.; Allevato, V. et al.
Item Type: Refine your search to only Article
Partner: UNT College of Science
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