Book contents
- Frontmatter
- Contents
- Index of Participants
- Preface
- I Evidence and Implications of Anisotropy in AGN
- II Luminosity Functions and Continuum Energy Distributions
- III The Broad Line Region: Variability and Structure
- Emission Line and Continuum Variability in Active Galactic Nuclei
- Results of the LAG Monitoring Campaign
- A Relation Between the Profiles and Intensities of Broad Emission Lines
- Broad Line Profile Variability in NGC 4593
- Deconvolution of Variable Seyfert 1 Profiles
- Ultra-violet Variability of AGN
- Broad-Line Variations in NGC 5548
- NGC 4593: A Low Luminosity Compact Seyfert 1 Nucleus
- UV Continuum Origin and BLR Structure in F-9
- UV Emission Line Intensities and Variability: a Self Consistent Model for Broad-Line Emitting Gas in NGC 3783
- Non-Linear Anisotropic BLR Models
- Anisotropic Line Emission from Extended BLR's
- Active Galactic Nuclei and Nuclear Starbursts
- Rapidly Evolving Compact SNRs and the Nature of the Lag in AGNs
- Supernova Explosions in QSOs? - II
- High Metallicities in QSOs
- The Chemical Evolution of QSOs
- Non-Linearity of Ly α Response in Variable AGNs
- Implications of Broad Line Profile Diversity among AGN
- Emission Line Studies of AGN
- A Search for Velocity Shifts in QSO Broad Lines
- Broad Line Region Structure from Profile Shapes
- IV X-rays and Accretion Disks
- V Beams, Jets and Blazars
- VI Concluding Talk
Anisotropic Line Emission from Extended BLR's
from III - The Broad Line Region: Variability and Structure
Published online by Cambridge University Press: 04 August 2010
- Frontmatter
- Contents
- Index of Participants
- Preface
- I Evidence and Implications of Anisotropy in AGN
- II Luminosity Functions and Continuum Energy Distributions
- III The Broad Line Region: Variability and Structure
- Emission Line and Continuum Variability in Active Galactic Nuclei
- Results of the LAG Monitoring Campaign
- A Relation Between the Profiles and Intensities of Broad Emission Lines
- Broad Line Profile Variability in NGC 4593
- Deconvolution of Variable Seyfert 1 Profiles
- Ultra-violet Variability of AGN
- Broad-Line Variations in NGC 5548
- NGC 4593: A Low Luminosity Compact Seyfert 1 Nucleus
- UV Continuum Origin and BLR Structure in F-9
- UV Emission Line Intensities and Variability: a Self Consistent Model for Broad-Line Emitting Gas in NGC 3783
- Non-Linear Anisotropic BLR Models
- Anisotropic Line Emission from Extended BLR's
- Active Galactic Nuclei and Nuclear Starbursts
- Rapidly Evolving Compact SNRs and the Nature of the Lag in AGNs
- Supernova Explosions in QSOs? - II
- High Metallicities in QSOs
- The Chemical Evolution of QSOs
- Non-Linearity of Ly α Response in Variable AGNs
- Implications of Broad Line Profile Diversity among AGN
- Emission Line Studies of AGN
- A Search for Velocity Shifts in QSO Broad Lines
- Broad Line Region Structure from Profile Shapes
- IV X-rays and Accretion Disks
- V Beams, Jets and Blazars
- VI Concluding Talk
Summary
Due to the combination of high radiation densities in the BLR and the high column densities of clouds which are optically thick to the Lyman continuum, many lines emitted from the BLR are likely to be optically thick, and hence will be emitted anisotropically. Ferland et al. (1992) discussed the case where the amount of anisotropy is constant for all clouds, but in reality the anisotropy will vary for a spatially extended BLR, depending on the local physical conditions. To study this effect, we have computed several models for spherical BLR's populated by an ensemble of spherical clouds in pressure balance with an intercloud medium, using our BLR modelling code, PROSYN (Goad, O'Brien & Gondhalekar 1993), which utilizes the photoionization code CLOUDY (Ferland 1991). Here we show some of the results for a constant pressure BLR model, where the cloud density (N) and column density (Ncol) are constant with radius (r), and hence the ionization parameter (U) varies as r−2. The model was normalized to have N = 1010 cm−3, Ncol = 1023.75 cm−2 and U = 10−2 at a radius of 10 light-days. The inner and outer radii were set at 0.3 and 56.2 light-days respectively, giving a range in log U from 1.0 to −3.5.
The total line emissivity εtotl = εin + εout, where εin is the emissivity of the inward cloud face (towards the ionizing continuum source) and εout is the outward emissivity (away from the ionizing continuum source).
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- The Nature of Compact Objects in Active Galactic NucleiProceedings of the 33rd Herstmonceux Conference, held in Cambridge, July 6-22, 1992, pp. 207 - 208Publisher: Cambridge University PressPrint publication year: 1994