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Title: 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

We consider how the profile and multi-year variability properties of a large sample of C IV Broad Absorption Line (BAL) troughs change when BALs from Si IV and/or Al III are present at corresponding velocities, indicating that the line of sight intercepts at least some lower ionization gas. We derive a number of observational results for C IV BALs separated according to the presence or absence of accompanying lower ionization transitions, including measurements of composite profile shapes, equivalent width (EW), characteristic velocities, composite variation profiles, and EW variability. We also measure the correlations between EW and fractional-EW variability for C IV, Si IV, and Al III. Our measurements reveal the basic correlated changes between ionization level, kinematics, and column density expected in accretion-disk wind models; e.g., lines of sight including lower ionization material generally show deeper and broader C IV troughs that have smaller minimum velocities and that are less variable. Many C IV BALs with no accompanying Si IV or Al III BALs may have only mild or no saturation.
Authors:
; ; ;  [1] ;  [2] ;  [3] ;  [4] ;  [5] ;  [6] ;  [7] ;  [8] ;  [9] ;  [10]
  1. Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States)
  2. Department of Physics and Astronomy, York University, 4700 Keele Street, Toronto, Ontario M3J 1P3 (Canada)
  3. Astronomy Department, University of Washington, Seattle, WA 98195 (United States)
  4. Department of Astronomy, University of Florida, Gainesville, FL 32611-2055 (United States)
  5. Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States)
  6. Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago (Chile)
  7. Institut d'Astrophysique de Paris, Universite Paris 6, F-75014 Paris (France)
  8. Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States)
  9. Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)
  10. Department of Astronomy and Astrophysics, The University of Chicago, Chicago, IL 60637 (United States)
Publication Date:
OSTI Identifier:
22365318
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 791; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ABSORPTION; ACCRETION DISKS; ALUMINIUM; CARBON; CORRELATIONS; DENSITY; ELEMENT ABUNDANCE; IONIZATION; QUASARS; SATURATION; SILICON; STELLAR WINDS; VELOCITY