Published in "QSO Absorption Lines", Space
Telescope Science Institute Symposium Series 2, 1987, eds. J. C. Blades,
D. A. Turnshek and C. A. Norman
BAL QSOs: OBSERVATIONS, MODELS AND IMPLICATIONS
FOR NARROW ABSORPTION LINE SYSTEMS
David A. Turnshek
Space Telescope Science
Institute, Baltimore
Abstract. The current status of observations pertaining to BAL
QSOs is reviewed.
Evidence which motivates a simple disk-like geometric and kinematic
model for the
BAL region is presented. This includes constraints on distance, covering
factor and the
acceleration/deceleration of the BAL region flow. Evidence which
suggests that BAL region abundances are enhanced relative to solar
values is also reviewed. The relation
between this model and models for QSO broad and narrow emission line
regions is discussed. Finally, evidence which suggests that some of the
narrow absorption line
systems seen in QSO spectra are intrinsic or caused by the BAL phenomenon is
considered.
Table of Contents
INTRODUCTION
- OBSERVATIONS
- Fraction of QSOs with BALs
- Characteristics of BALs
- Correlation Between BAL and Broad Emission Line
Profiles
- Emission Line Properties of BAL QSOs
- Radio Properties of BAL QSOs
- Optical Polarization and Variability of BAL QSOs
- BAL Trough Variability
- Imaging of BAL QSOs
- MODEL PROPERTIES
- The Starting Point of a Model
- The Size Scale of the BAL Region
- The Global BAL Region Covering Factor
- The Large and Small Scale Geometry of the BAL
Region
- Is the BAL Region Flow Accelerating or
Decelerating?
- Abundances and Ionization in the BAL Region
- Relation Between the BAL Region and the Emission
Line Regions
- RELATION TO THE NARROW ABSORPTION LINES
- Similarity Between the BALs and the Narrow
Absorption Lines
- Zabs Near
Zem Systems
- Highly Displaced Metal Line Systems
- Damped
Ly-
Systems
- Ly- Forest Systems
- The Effect of the BAL Region Outflow
- FUTURE WORK
- REFERENCES
