X-ray and multi-epoch optical/UV investigations of BAL to non-BAL quasar transformations

Abstract

We report on an X-ray and optical/UV study of eight Broad Absorption Line (BAL) to non-BAL transforming quasars at $z\approx$1.7-2.2 over 0.29-4.95 rest-frame years with at least three spectroscopic epochs for each quasar from the SDSS, BOSS, $Gemini$, and ARC 3.5-m telescopes. New $Chandra$ observations obtained for these objects show their values of ${\alpha }_{\mathrm{ox}}$ and $\Delta {\alpha }_{\mathrm{ox}}$, as well as their spectral energy distributions, are consistent with those of non-BAL quasars. Moreover, our targets have X-ray spectral shapes that are, on average, consistent with weakened absorption with an effective power-law photon index of ${\Gamma }_{\mathrm{eff}}=1.69_{-0.25}^{+0.25}$. The newer $Gemini$ and ARC 3.5-m spectra reveal that the BAL troughs have remained absent since the BOSS observations where the BAL disappearance was discovered. The X-ray and optical/UV results in tandem are consistent with at least the X-ray absorbing material moving out of the line-of-sight, leaving an X-ray unabsorbed non-BAL quasar. The UV absorber might have become more highly ionized (in a shielding-gas scenario) or also moved out of the line-of-sight (in a wind-clumping scenario).

arXiv comment14 pages, 5 figures, Accepted for publication in MNRAS

References in corpus (76)

• The Sloan Digital Sky Survey: Technical Summary
• The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance
• Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
• The 2.5 m Telescope of the Sloan Digital Sky Survey
• SDSS-III: Massive Spectroscopic Surveys of the Distant Universe, the Milky Way Galaxy, and Extra-Solar Planetary Systems
• The Baryon Oscillation Spectroscopic Survey of SDSS-III
• A Catalog of Quasar Properties from SDSS DR7
• Spectral Energy Distributions and Multiwavelength Selection of Type 1 Quasars
• The Multi-Object, Fiber-Fed Spectrographs for SDSS and the Baryon Oscillation Spectroscopic Survey
• Dynamics of line-driven disk winds in Active Galactic Nuclei
• Modeling the Time Variability of SDSS Stripe 82 Quasars as a Damped Random Walk
• Powerful Outflows and Feedback from Active Galactic Nuclei
• A Wavelet-Based Algorithm for the Spatial Analysis of Poisson Data
• The Chandra Deep Field-South Survey: 4 Ms Source Catalogs
• The X-ray-to-Optical Properties of Optically-Selected Active Galaxies Over Wide Luminosity and Redshift Ranges
• The X-ray Properties of the Most-Luminous Quasars from the Sloan Digital Sky Survey
• A Catalog of Broad Absorption Line Quasars from the Sloan Digital Sky Survey Third Data Release
• A Catalog of Broad Absorption Line Quasars in Sloan Digital Sky Survey Data Release 5
• Unusual Broad Absorption Line Quasars from the Sloan Digital Sky Survey
• On the Nature of Soft X-ray Weak Quasi-Stellar Objects
• Optical Continuum and Emission-Line Variability of Seyfert 1 Galaxies
• The Hard X-ray Spectrum as a Probe for Black-Hole Growth in Radio-Quiet Active Galactic Nuclei
• Dust Reddening in SDSS Quasars
• A strong redshift dependence of the broad absorption line quasar fraction
• X-ray Spectroscopy of QSOs with Broad Ultraviolet Absorption Lines
• An Exploratory Chandra Survey of a Well-Defined Sample of 35 Large Bright Quasar Survey Broad Absorption Line Quasars
• X-ray Insights into the Nature of PHL 1811 Analogs and Weak Emission-Line Quasars: Unification with a Geometrically Thick Accretion Disk?
• A Chandra Survey of Broad Absorption Line Quasars
• Broad Absorption Line Variability on Multi-Year Timescales in a Large Quasar Sample
• XMM-Newton spectroscopy of high-redshift QSOs
• The young stellar population in M17 revealed by Chandra
• Broad Absorption Line Disappearance on Multi-Year Timescales in a Large Quasar Sample
• Are Optically-Selected Quasars Universally X-Ray Luminous? X-Ray/UV Relations in Sloan Digital Sky Survey Quasars
• Line-driven Disk Winds in Active Galactic Nuclei: The Critical Importance of Ionization and Radiative Transfer
• Broad Absorption Line QSOs Observed by the ROSAT PSPC
• Chandra Observations of the Highest Redshift Quasars from the Sloan Digital Sky Survey
• Broad Absorption Line Variability in Repeat Quasar Observations from the Sloan Digital Sky Survey
• Tombaugh 2: The First Open Cluster with a Significant Abundance Spread or Embedded in a Cold Stellar Stream?
• Variability in quasar broad absorption line outflows II. Multi-epoch monitoring of SiIV and CIV BAL variability
• Confirmation of and Variable Energy Injection by a Near-Relativistic Outflow in APM 08279+5255
• Implications of Dramatic Broad Absorption Line Variability in the Quasar FBQS J1408+3054
• Variability in Quasar Broad Absorption Line Outflows III. What Happens on the Shortest Time-scales?
• Extreme-Velocity Quasar Outflows and the Role of X-ray Shielding
• The XMM-SERVS survey: new XMM-Newton point-source catalog for the XMM-LSS field
• Emergence of a Broad-Absorption-Line Outflow in the Narrow-line Seyfert 1 Galaxy WPVS 007
• A non-hydrodynamical model for acceleration of line-driven winds in Active Galactic Nuclei
• The Sloan Digital Sky Survey Reverberation Mapping Project: Rapid CIV Broad Absorption Line Variability
• Weak Hard X-ray Emission from Two Broad Absorption Line Quasars Observed with NuSTAR: Compton-thick Absorption or Intrinsic X-ray Weakness?
• Testing Quasar Unification: Radiative Transfer in Clumpy Winds
• Radio Through X-ray Spectral Energy Distributions of 38 Broad Absorption Line Quasars
• Evolution of the X-ray Emission of Radio-Quiet Quasars
• LBQS 0103-2753: A 0.3 Arcsec Binary Quasar
• Dramatic X-ray Spectral Variability of the Broad Absorption Line Quasar PG2112+059
• A Simple Disk Wind Model for Broad Absorption Line Quasars
• New constraints on the X-ray spectral properties of type 1 AGN
• The Dependence of C IV Broad Absorption Line Properties on Accompanying Si IV and Al III Absorption: Relating Quasar-Wind Ionization Levels, Kinematics, and Column Densities
• Broad absorption line disappearance and emergence using multiple-epoch spectroscopy from the Sloan Digital Sky Survey
• Radiation pressure confinement - IV. Application to broad absorption line outflows
• XMM-Newton Observations of Two BAL QSOs: Q1246-057 and SBS1542+541
• Thomson Thick X-ray Absorption in a Broad Absorption Line Quasar PG0946+301
• The quest for Type 2 quasars: Chandra observations of luminous obscured quasars in the Sloan Digital Sky Survey
• The Long-Term X-Ray Variability of Broad Absorption Line Quasars
• The Transition from "Normal" to "Broad Absorption Line Quasar" of Ton 34
• Dynamically evolving Mg II broad absorption line flow in SDSS J133356.02+001229.1
• The Correlation between X-ray and UV Properties of BAL QSOs
• X-Ray Absorption and an X-Ray Jet in the Radio-Loud Broad Absorption Line Quasar PG 1004+130
• Correlation between the variation of the ionizing continuum and broad absorption lines
• Variable Reddening and Broad Absorption Lines in the Narrow-line Seyfert 1 Galaxy WPVS 007: an Origin in the Torus
• A multi-epoch spectroscopic study of the BAL quasar APM 08279+5255 II. Emission- and absorption-line variability time lags
• Emergence and Variability of Broad Absorption Line Quasar Outflows
• Discovery of Newly Formed Broad Absorption Lines in a Radio-Loud Quasar
• Strong Variability of Overlapping Iron Broad Absorption Lines in Five Radio-selected Quasars
• C IV BAL disappearance in a large SDSS QSO sample
• The X-Ray Properties of the Optically Brightest Mini-BAL Quasars from the Sloan Digital Sky Survey
• Transient C IV Broad Absorption Lines in radio detected QSOs
• X-ray and optical properties of Broad Absorption Line Quasars in the Canada-France-Hawaii Telescope Legacy Survey

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• BAL and non-BAL quasars: continuum, emission and absorption properties establish a common parent sample
• The correlations between optical/UV broad lines and X-ray emission for a large sample of quasars
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• Deep XMM-Newton Observations of an X-ray Weak, Broad Absorption Line Quasar at $z=6.5$
• Broad absorption line disappearance/emergence in multiple ions in a weak emission-line quasar
• Multi-epoch spectroscopy of Mg II broad absorption line transitions
• Coordinated X-ray and UV absorption within the accretion disk wind of the active galactic nucleus PG 1126-041
• A New Member of the Fast and Furious Family: A Relativistic and Time-Variable UV Outflow in a Luminous Quasar