Published in "Active Galactic Nuclei", eds. R.D. Blandford, H. Netzer and L. Woltjer, 1990.

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Table of Contents

• THEORETICAL MODELS
• The BLR and the NLR
• Photoionization Models
• Other Models
• Bibliography
• PHOTOIONIZATION MODELS FOR ISOLATED CLOUDS
• Photoionization equilibrium
• Thermal Equilibrium
• Additional Heating and Ionization Processes
• Radiative Transfer
• The Emergent Spectrum
• Bibliography
• PHOTOIONIZATION MODELS FOR A SYSTEM OF CLOUDS
• Spherical BLR Models
• Non-spherical Models
• Bibliography
• COMPARISON WITH THE OBSERVATIONS
• The Broad Line Region
• The Narrow Line Region
• The Energy Budget of the BLR
• Bibliography
• DUST AND REDDENING
• Thermal Emission and Polarization
• Internal and External Dust
• Dust and Reddening in the NLR
• Dust and Reddening in the BLR
• Continuum Reddening
• Bibliography
• LINE AND CONTINUUM VARIABILITY: MAPPING THE BLR
• Line and Continuum Light Curves
• Cross Correlation
• The Transfer Function
• Light Curve Modeling
• The BLR Size
• Anisotropic Emission and Beaming
• Bibliography
• GAS MOTION AND DYNAMICS
• Confined Cloud Models
• Other Models
• Observed Line Profiles
• Theoretical Line Profiles
• Cross-correlation Tests
• Bibliography
• LINE AND CONTINUUM CORRELATIONS
• Line Intensity vs. Continuum Luminosity
• Line - Line Correlations
• Line Width vs. Continuum Luminosity: M/L for AGNs
• The Baldwin Relationship
• AGN Accretion Disks
• QUASARS, MINIQUASARS AND MICROQUASARS
• Narrow Line X-ray Galaxies
• Seyfert 2 Galaxies
• LINERs
• AGN Classification: QI, QII and QIII
• Bibliography
• REFERENCES
• LIST OF SYMBOLS